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TUR-06 Turtle Assessment — named Turtle
Part 6 · Python Turtle (named Turtle)
Check understanding across the complete Python Turtle unit through theory and practical application. Students will: - demonstrate secure knowledge of named-Turtle instructions - reason about loops, variables and functions - apply their learning in practical code Inside: a 25-mark mix of objective, written and coding questions. Series: Python Turtle (named Turtle), part 6 of 6.
WorksheetTUR-05 Turtle Review — named Turtle
Part 5 · Python Turtle (named Turtle)
Consolidate the main named-Turtle programming ideas before the end-of-unit assessment. Students will: - review movement, turns and pen controls - apply loops and variables to drawing problems - practise reusable drawing functions Inside: retrieval questions, objective checks and practical revision tasks. Series: Python Turtle (named Turtle), part 5 of 6.
WorksheetTUR-04 Turtle Scene Project — named Turtle
Part 4 · Python Turtle (named Turtle)
Plan and build a complete scene with a named Turtle by combining the techniques developed so far. Students will: - break a larger drawing into manageable parts - reuse patterns and drawing ideas - test and improve a complete scene Inside: planning prompts, staged coding and a practical Turtle project. Series: Python Turtle (named Turtle), part 4 of 6.
WorksheetTUR-03 Colourful Canvas — named Turtle
Part 3 · Python Turtle (named Turtle)
Explore colour and pen controls with a named Turtle while building expressive drawings. Students will: - change pen and fill colours - control pen width and drawing state - combine repetition with visual choices Inside: guided examples, knowledge checks and colourful coding tasks. Series: Python Turtle (named Turtle), part 3 of 6.
WorksheetTUR-02 Shape Machine — named Turtle
Part 2 · Python Turtle (named Turtle)
Use repetition to turn a sequence of named-Turtle instructions into regular shapes. Students will: - identify the repeated steps in a shape - use counting loops to reduce repeated code - control a shape with variables Inside: worked examples, objective checks and practical Turtle challenges. Series: Python Turtle (named Turtle), part 2 of 6.
WorksheetTUR-01 Turtle Steps — named Turtle
Part 1 · Python Turtle (named Turtle)
Build confidence with a named Python Turtle by turning movement instructions into simple drawings. Students will: - create and control a named Turtle object - combine movement instructions in the correct sequence - store useful drawing values in variables Inside: guided Turtle examples, short checks and practical coding tasks. Series: Python Turtle (named Turtle), part 1 of 6.
WorksheetTUR-06 Turtle Assessment — direct functions
Part 6 · Python Turtle (direct functions)
Check understanding across the complete Python Turtle unit through theory and practical application. Students will: - demonstrate secure knowledge of Turtle instructions - reason about loops, variables and functions - apply their learning in practical code Inside: a 25-mark mix of objective, written and coding questions. Series: Python Turtle (direct functions), part 6 of 6.
WorksheetTUR-05 Turtle Review — direct functions
Part 5 · Python Turtle (direct functions)
Consolidate the main Turtle programming ideas before the end-of-unit assessment. Students will: - review movement, turns and pen controls - apply loops and variables to drawing problems - practise reusable drawing functions Inside: retrieval questions, objective checks and practical revision tasks. Series: Python Turtle (direct functions), part 5 of 6.
WorksheetTUR-04 Turtle Scene Project — direct functions
Part 4 · Python Turtle (direct functions)
Plan and build a complete Turtle scene by combining the techniques developed so far. Students will: - break a larger drawing into manageable parts - reuse patterns and drawing ideas - test and improve a complete scene Inside: planning prompts, staged coding and a practical Turtle project. Series: Python Turtle (direct functions), part 4 of 6.
WorksheetTUR-03 Colourful Canvas — direct functions
Part 3 · Python Turtle (direct functions)
Explore Turtle colour and pen controls while building increasingly expressive drawings. Students will: - change pen and fill colours - control pen width and drawing state - combine repetition with visual choices Inside: guided examples, knowledge checks and colourful coding tasks. Series: Python Turtle (direct functions), part 3 of 6.
WorksheetTUR-02 Shape Machine — direct functions
Part 2 · Python Turtle (direct functions)
Use repetition to turn a sequence of Turtle instructions into regular shapes. Students will: - identify the repeated steps in a shape - use counting loops to reduce repeated code - control a shape with variables Inside: worked examples, objective checks and practical Turtle challenges. Series: Python Turtle (direct functions), part 2 of 6.
WorksheetTUR-01 Turtle Steps — direct functions
Part 1 · Python Turtle (direct functions)
Build confidence with Python Turtle by turning movement instructions into simple drawings. Students will: - use forward movement and turns to control a Turtle - combine instructions in the correct sequence - store useful drawing values in variables Inside: guided Turtle examples, short checks and practical coding tasks. Series: Python Turtle (direct functions), part 1 of 6.
WorksheetOCR H446 1.1.1 Word size, bus width and addressable memory
Part 12 · H446 1.1.1 · Structure and function of the processor
OCR H446 1.1.1: Word size, bus width and addressable memory. Students learn to distinguish word size, address-bus width and data-bus width, then calculate addressable capacity; word size has been credited in OCR sample assessment marking, but it is not named as a standalone specification or content-guide point. Students will: - distinguish word size, address-bus width and data-bus width - calculate addressable memory capacity - apply the model to unfamiliar values and diagnose incorrect claims Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 21 marks, about 25 to 35 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 12 of 12.
WorksheetOCR H446 2.3.1 Algorithms exam transition
Part 16 · H446 2.3.1 · Algorithms
This is the assessment piece that closes H446 2.3.1: students work independently across one volunteering-platform scenario, without checking answers as they go, and feedback is held until after submission. At 80 marks it is best used as a mock or an end-of-topic check rather than a lesson activity. Students will: - design pseudocode for a sentinel-controlled input routine and handle the empty case - explain the growth classes by what happens as the input grows, correcting a stock error - perform a binary search and an insertion sort by hand, showing intermediate state - implement linear search and a non-destructive bubble sort that cope with empty lists - calculate shortest distances and A star selections, then cite evidence for what to revisit Inside: 3 explanation cells, 9 written answers and 1 Python task. 80 marks, about 75 to 90 minutes. Series: H446 2.3.1 · Algorithms, part 16 of 16.
WorksheetOCR H446 2.3.1 Algorithms consolidation
Part 15 · H446 2.3.1 · Algorithms
Everything in H446 2.3.1 meets here in one interleaved worksheet: representation, growth, searches, sorts, stacks, queues, linked lists, traversals and pathfinding, with no new content introduced. It is designed for the point in the course where students can each do the parts but choose the wrong method when the topic label is removed. Students will: - correct a cluster of common misstatements about growth and running time - sort the same list twice by different methods and give a case-sensitive point for each - trace a stack-like process and contrast it with circular queue and linked-list updates - set out traversal orders with their controlling structures and the effect of graph cycles - plan and justify algorithms for a four-part route planner with preconditions and tests Inside: 4 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 6 written answers and 1 trace table. 57 marks, about 60 to 80 minutes. Series: H446 2.3.1 · Algorithms, part 15 of 16.
WorksheetOCR H446 2.3.1 A star and heuristics
Part 14 · H446 2.3.1 · Algorithms
A star is not Dijkstra with relabelled numbers, and H446 2.3.1 expects students to calculate g, h and f and to say what the heuristic is doing to the search. This worksheet works the selection rule through frontier scores, then tests three different heuristics on the same nodes so students can see informativeness and overestimation as separate issues. Students will: - calculate g, h and f for frontier nodes and select the next node from them - recalculate a selection after a cheaper route lowers a node's known cost - compare A star with Dijkstra on goal information, nodes explored and stopping - judge whether given heuristic values would still allow an optimal result - explain what a zero heuristic does to the search and the risk in an overestimate Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 3 written answers. 28 marks, about 30 to 45 minutes. Series: H446 2.3.1 · Algorithms, part 14 of 16.
WorksheetOCR H446 2.3.1 Dijkstra shortest paths
Part 13 · H446 2.3.1 · Algorithms
Dijkstra appears in H446 2.3.1 as something students calculate and trace rather than write from scratch, so the examined skill is holding tentative distances, later improvements and predecessors accurately. This worksheet keeps that whole state visible on a weighted graph and finishes with students building and verifying a graph of their own. Students will: - maintain tentative and final distances alongside a predecessor for each node - record every improvement made to a distance when a shorter route is offered - give a finalisation order and reconstruct a shortest path from the predecessors - diagnose selecting the smallest edge, settling a node too early and negative weights - design a five-node graph with competing routes and verify the result by summing edges Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 3 written answers and 1 trace table. 32 marks, about 30 to 45 minutes. Series: H446 2.3.1 · Algorithms, part 13 of 16.
WorksheetOCR H446 2.3.1 Post-order DFS and breadth-first traversal
Part 12 · H446 2.3.1 · Algorithms
H446 2.3.1 names post-order depth-first and breadth-first traversal specifically, and each is controlled by a different structure: recursion or an explicit stack for one, a queue for the other. This worksheet produces both orders by hand with the queue state written out, then transfers the same algorithms to a graph where repeats become possible. Students will: - produce post-order depth-first and breadth-first orders for a rooted tree - name the controlling structure behind each traversal and say why it fits - show queue states as a breadth-first traversal proceeds, including an added child - implement both traversals, marking discovered nodes when running on a graph - compare the memory demands and typical uses of the two traversals Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 1 Python task. 29 marks, about 25 to 40 minutes. Series: H446 2.3.1 · Algorithms, part 12 of 16.
WorksheetOCR H446 2.3.1 Tree operations
Part 11 · H446 2.3.1 · Algorithms
Tree questions in H446 2.3.1 depend on the policy in force: a binary tree limits children to two, while a binary search tree adds the ordering rule that makes searching possible. This worksheet separates those two ideas, then works insertion, search and the awkward two-child deletion under an explicit rule. Students will: - distinguish the binary tree definition from the additional ordering rule of a BST - follow and record a comparison path down to the null child where a value belongs - delete leaf, one-child and two-child nodes using a consistently chosen replacement - implement an iterative BST search over nodes held as dictionaries - explain how insertion order can flatten a tree into a chain and what that costs Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 1 Python task. 25 marks, about 25 to 40 minutes. Series: H446 2.3.1 · Algorithms, part 11 of 16.
WorksheetOCR H446 2.3.1 Linked-list algorithms
Part 10 · H446 2.3.1 · Algorithms
Linked-list algorithms in H446 2.3.1 follow links rather than physical positions, so the marks turn on the order in which pointers are reassigned. This worksheet sets out safe insertion and removal order, then has students traverse a list whose indexes are deliberately out of physical sequence. Students will: - traverse and search a list by following next pointers rather than array order - work with parallel value and next-index arrays where logical order differs from storage - order pointer assignments so the remainder of the list stays reachable - insert and remove nodes at the head, middle and end, handling the empty case - explain why reaching the kth item costs more than inserting after a known node Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers, 1 Python task and 1 trace table. 21 marks, about 25 to 40 minutes. Series: H446 2.3.1 · Algorithms, part 10 of 16.
WorksheetOCR H446 2.3.1 Stack and queue algorithms
Part 9 · H446 2.3.1 · Algorithms
Here H446 2.3.1 algorithm work meets the structures from 1.4.2: push, pop, enqueue and dequeue, all of which depend on stated pointer conventions before a trace can be marked. The worksheet is the longest in the series because students both trace circular wrap-around and implement the operations, including the overflow and underflow checks. Students will: - state head, tail, top and count conventions before performing any operation - trace a circular queue across a wrap-around, giving the state after each operation - explain why a circular dequeue should not shift the remaining items - implement array stack push and pop, and circular queue enqueue and dequeue - diagnose faulty operation order and the effect of calling a helper twice Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers, 2 Python tasks and 1 trace table. 37 marks, about 45 to 70 minutes. Series: H446 2.3.1 · Algorithms, part 9 of 16.
WorksheetOCR H446 2.3.1 Quick sort
Part 8 · H446 2.3.1 · Algorithms
Quick sort answers in H446 2.3.1 are only markable when the pivot and partition convention are stated, because different conventions produce different intermediate lists. This worksheet supplies one explicit convention, works a full set of recursive partitions with it, then turns to why pivot choice decides whether the algorithm scales well or badly. Students will: - apply a supplied pivot and partition convention consistently through a trace - show every recursive partition produced when sorting an eight-item list by hand - implement quick sort in Python under the stated convention - link balanced and repeatedly extreme pivots to the resulting growth behaviour - compare quick sort with merge sort on timing, pivot sensitivity and extra storage Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 1 Python task. 27 marks, about 25 to 40 minutes. Series: H446 2.3.1 · Algorithms, part 8 of 16.
WorksheetOCR H446 2.3.1 Merge sort
Part 7 · H446 2.3.1 · Algorithms
Merge sort is the H446 2.3.1 divide-and-conquer example, and the difficulty is rarely the splitting; it is the merge loop, where students lose track of which values have been consumed. This worksheet makes both the recursive structure and every merge-loop state visible before asking for an implementation and a memory trade-off judgement. Students will: - model the recursive split down to base cases and the combination back up - show the complete split and merge states for a small list by hand - trace a merge loop index by index, including the condition that ends it - implement splitting and merging so no unconsumed value is lost - explain the predictable scaling of merge sort against its extra memory demand Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers, 1 Python task and 1 trace table. 26 marks, about 25 to 40 minutes. Series: H446 2.3.1 · Algorithms, part 7 of 16.
WorksheetOCR H446 2.3.1 Bubble and insertion sort
Part 6 · H446 2.3.1 · Algorithms
Bubble and insertion sort are both in-place and both examined in H446 2.3.1, yet they rest on different mental models: adjacent swaps across passes against a growing sorted partition. Keeping those models distinct is what this worksheet drills, through hand traces, implementations and a comparison on favourable and unfavourable data. Students will: - say what one complete bubble pass guarantees about the data - show every state of an insertion sort, marking the sorted and unsorted partitions - trace a full bubble process including the swap flag that allows an early exit - implement both sorts in Python with early exit and shifting behaviour - compare the two on already sorted and reverse-sorted input Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers, 1 Python task and 1 trace table. 29 marks, about 30 to 45 minutes. Series: H446 2.3.1 · Algorithms, part 6 of 16.
WorksheetOCR H446 2.3.1 Linear and binary search
Part 5 · H446 2.3.1 · Algorithms
Binary search is examined in H446 2.3.1 alongside linear search, and the mark is usually lost on the precondition or on bounds that drift during a trace. This worksheet has students search by hand, trace the shrinking bounds, write both algorithms in Python and then pick the right one for a stated situation. Students will: - state the precondition that makes discarding half a list safe - trace low, high and middle values while a search narrows towards a target - record every compared value when searching the same data both ways - implement linear and binary search that return an index or minus one - recommend a search for a short one-off list and for a large maintained catalogue Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers, 1 Python task and 1 trace table. 25 marks, about 25 to 40 minutes. Series: H446 2.3.1 · Algorithms, part 5 of 16.
WorksheetOCR H446 2.3.1 Best, average and worst cases
Part 4 · H446 2.3.1 · Algorithms
Input size is not the whole story: arrangement and target position change the work done, which is the distinction H446 2.3.1 draws between best, average and worst cases. The worksheet insists that every case claim carries its assumptions, and keeps cases apart from the growth classes students meet alongside them. Students will: - define best, average and worst by describing the input condition that produces each - identify the arrangements that give insertion sort its least and most shifting work - state the algorithm version, size, arrangement and counted operation behind any claim - critique a statement that mixes a case up with a complexity class - construct concrete inputs for a stopping condition and draw growth conclusions from them Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 3 written answers. 21 marks, about 20 to 30 minutes. Series: H446 2.3.1 · Algorithms, part 4 of 16.
WorksheetOCR H446 2.3.1 Big O growth
Part 3 · H446 2.3.1 · Algorithms
Big O is where H446 2.3.1 students most often reach for the right words with the wrong meaning. This worksheet builds constant, logarithmic, linear, polynomial and exponential growth from what actually happens to the work when the input size changes, and asks students to read growth from code structure and from a graph. Students will: - classify expressions and code shapes into the five growth families - explain a curve by saying what happens when the input size doubles - trace a counter and use the count to identify the growth family - repair common misstatements about exponential and logarithmic work - explain why a growth class alone does not predict runtime on small inputs Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 3 written answers and 1 trace table. 26 marks, about 25 to 35 minutes. Series: H446 2.3.1 · Algorithms, part 3 of 16.
WorksheetOCR H446 2.3.1 Algorithm suitability, time and space
Part 2 · H446 2.3.1 · Algorithms
A correct algorithm can still be the wrong one to use, and H446 2.3.1 expects students to argue suitability against execution time, memory and the situation the algorithm runs in. This worksheet gives students a repeatable comparison frame so recommendations are tied to data and context rather than a claim that one method is simply faster. Students will: - distinguish whether an algorithm is correct from whether it is suitable here - describe how dominant work and extra storage grow with the number of items - weigh preprocessing and update costs against the number of times a task is repeated - recommend an approach for a repeatedly searched school list that changes overnight - justify a choice for a memory-limited sensor that receives one reading at a time Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 3 written answers. 22 marks, about 20 to 30 minutes. Series: H446 2.3.1 · Algorithms, part 2 of 16.
WorksheetOCR H446 2.3.1 Designing and representing algorithms
Part 1 · H446 2.3.1 · Algorithms
OCR H446 2.3.1 opens with algorithm design, where students must produce finite, testable steps and then move the same logic between a flowchart, pseudocode and program code. This worksheet builds that habit from the start, so students learn that changing the notation must never quietly change what the algorithm does. Students will: - separate a problem statement into inputs, validation, processing and outputs - rewrite the same logic as pseudocode and describe how its decisions appear in a flowchart - keep decision, loop-back and update order identical across representations - design an algorithm for an unfamiliar charging rule with a cap and a rejection condition - choose normal, boundary and invalid test cases with expected outputs Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 2 written answers. 20 marks, about 20 to 30 minutes. Series: H446 2.3.1 · Algorithms, part 1 of 16.
WorksheetOCR H446 2.2.2 Computational Methods exam transition
Part 14 · H446 2.2.2 · Computational methods
This is an assessment rather than a teaching worksheet: it covers the whole of H446 2.2.2 under examination conditions, with feedback held until after submission and no prompting about which method applies. Sixty marks run from a one-mark identification to a twelve-mark evaluation, taking in a trace table and a coded task on the way. Students will: - select the computational method a described problem calls for, unprompted - complete a trace table for an unseen backtracking search - construct a working coded solution under assessment conditions - apply each explanation to the scenario rather than writing a generic definition - reach a supported judgement in an extended evaluation of a proposal Inside: 2 explanation cells, 1 multiple-choice question, 8 written answers, 1 Python task and 1 trace table. 60 marks, about 65 to 75 minutes. Series: H446 2.2.2 · Computational methods, part 14 of 14.
WorksheetOCR H446 2.2.2 Computational Methods consolidation
Part 13 · H446 2.2.2 · Computational methods
Interleaved revision across the whole of H446 2.2.2, this worksheet deliberately mixes the methods so students have to recognise which one a problem calls for instead of practising each in turn. It runs from rapid retrieval through a backtracking trace and a coded heuristic to two extended evaluations, and introduces no new content. Students will: - match a described problem to the computational method at its centre - trace a backtracking search, then identify a dead end and the alternative explored next - implement a room-scoring heuristic with a defined tie rule - select and justify a different method for each of three needs in one scenario - evaluate combining a heuristic with a backtracking search on the same allocation problem Inside: 6 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells, 3 written answers, 1 Python task and 1 trace table. 37 marks, about 40 to 60 minutes. Series: H446 2.2.2 · Computational methods, part 13 of 14.
WorksheetOCR H446 2.2.2 Visualisation for understanding and planning
Part 12 · H446 2.2.2 · Computational methods
Visualisation earns marks in H446 2.2.2 only when the mapping is explained, so a diagram of labelled boxes will not do. Dependency graphs for a workflow give students something concrete to read, extend and judge, and the worksheet also draws the line between visualisation and abstraction. Students will: - state what each symbol and arrow in a visual representation stands for - read a dependency graph for ordering constraints and for work that could run concurrently - extend a diagram with a new task and explain what the added arrow means - explain how visualisation depends on abstraction without being the same idea - design a visualisation for a software release and evaluate how useful it would be Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 20 marks, about 20 to 30 minutes. Series: H446 2.2.2 · Computational methods, part 12 of 14.
WorksheetOCR H446 2.2.2 Software pipelining
Part 11 · H446 2.2.2 · Computational methods
Software pipelining is routinely confused with processor instruction pipelining, and only one of them is what H446 2.2.2 is asking about here. Stage timings from a media service give students the arithmetic behind a bottleneck, and the worksheet keeps latency and throughput firmly separate throughout. Students will: - explain stages, hand-offs and how different items occupy different stages at once - identify the bottleneck stage and estimate the best steady completion interval - separate the time taken by one item from the rate at which items complete - distinguish software pipelining from processor instruction pipelining - propose and justify a pipeline improvement, and name a correctness risk that overlapping introduces Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 20 marks, about 20 to 30 minutes. Series: H446 2.2.2 · Computational methods, part 11 of 14.
WorksheetOCR H446 2.2.2 Performance modelling
Part 10 · H446 2.2.2 · Computational methods
Software that works perfectly for one user can collapse under a thousand, which is the case for performance modelling in H446 2.2.2. A ticketing service under rising load supplies real-looking figures, and students read a table where response time climbs sharply while throughput barely moves. Students will: - distinguish performance modelling from testing whether features work correctly - interpret load, response time and throughput figures to infer a bottleneck - recommend a next investigation or design change justified by the evidence - specify loads, repeated trials, request mixes, measures and success thresholds for a model of their own - explain why passing a model does not prove the deployed system will meet its target Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 24 marks, about 25 to 35 minutes. Series: H446 2.2.2 · Computational methods, part 10 of 14.
WorksheetOCR H446 2.2.2 Programming and evaluating heuristics
Part 9 · H446 2.2.2 · Computational methods
H446 2.2.2 expects a heuristic to be transparent enough to test, so here the scoring rule becomes Python. Students implement job selection for a site-inspection team with a defined tie rule, design tests that isolate each part of the score, and then argue about what a new weighted term would do to the choices made. Students will: - translate a written scoring rule into a function that returns a score - implement a selection that returns the smallest-scoring option and keeps first-in-list order on a tie - design tests that isolate a single field, a boundary case and the tie rule - explain why examples chosen to match the code are weak evidence of correctness - assess the behaviour change, benefit, risk and evaluation of adding a weighted urgency term Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 1 written answer and 2 Python tasks. 18 marks, about 25 to 40 minutes. Series: H446 2.2.2 · Computational methods, part 9 of 14.
WorksheetOCR H446 2.2.2 Heuristics: informed estimates
Part 8 · H446 2.2.2 · Computational methods
A heuristic guides which option a search explores first without promising the best answer, and H446 2.2.2 examines exactly that distinction. Maintenance scheduling and rehearsal-room allocation give students scoring rules to calculate, a weighting to change, and a clear view of what the change costs. Students will: - define a heuristic and explain how it orders the options a search explores - calculate scores from a stated scoring rule and select the option it favours - compare two route estimates under stable conditions and under rapidly changing ones - explain how altering a weight shifts which options win, and which cases it disadvantages - evaluate a scoring rule against both solution quality and the cost of computing it Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 23 marks, about 20 to 30 minutes. Series: H446 2.2.2 · Computational methods, part 8 of 14.
WorksheetOCR H446 2.2.2 Evaluating data mining
Part 7 · H446 2.2.2 · Computational methods
Extended-response questions on data mining ask for far more than a list of benefits and drawbacks, which is where marks are usually lost. Written as examination practice on an anonymised travel-card scenario, this H446 2.2.2 worksheet builds claim, mechanism, application and consequence chains, then closes with a twelve-mark judgement and a self-review pass. Students will: - write an analytical paragraph linking a claim, a mechanism, an application and a consequence - plan a benefit chain and a limitation chain before answering a six-mark question - select the factors that matter most in a scenario instead of forcing in every prompt - produce an extended evaluation that reaches a stated and supported judgement - review their own writing for scenario evidence, mechanism words and unwarranted certainty Inside: 8 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 30 to 45 minutes. Series: H446 2.2.2 · Computational methods, part 7 of 14.
WorksheetOCR H446 2.2.2 Data mining: patterns from large data sets
Part 6 · H446 2.2.2 · Computational methods
Storing a great deal of data is not data mining, and H446 2.2.2 rewards students who can hold that line. A network of community venues supplies the booking records, and every finding here has to travel a chain from evidence to meaning to a decision the service could actually test. Students will: - distinguish collecting or storing large data sets from interrogating them to discover patterns - build a chain from a finding to a proposed decision and an outcome measure - state a relationship without claiming that one thing caused the other - identify limitations arising from missing, biased or inconsistent records - qualify a conclusion drawn from an unfamiliar data set and its context Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 20 marks, about 20 to 30 minutes. Series: H446 2.2.2 · Computational methods, part 6 of 14.
WorksheetOCR H446 2.2.2 Writing backtracking algorithms
Part 5 · H446 2.2.2 · Computational methods
Reading a backtracking template is far easier than writing one that terminates and restores its state correctly. This H446 2.2.2 worksheet moves students from the template to their own subset-sum implementation, by way of a debugging task built around the classic missing undo after a failed recursive call. Students will: - define the state, the alternatives, the success test and the failure test for a backtracking problem - explain when a running total exceeding the target is a safe failure test - diagnose how a missing undo step corrupts a later route or the returned path - implement a subset-sum search that uses each value at most once and leaves the input list unchanged - explain why the order of the include and exclude routes changes running time but not the set of solutions reachable Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 1 Python task. 22 marks, about 25 to 40 minutes. Series: H446 2.2.2 · Computational methods, part 5 of 14.
WorksheetOCR H446 2.2.2 Backtracking: decisions and dead ends
Part 4 · H446 2.2.2 · Computational methods
Backtracking is examined in H446 2.2.2 as a search that undoes its most recent choice, so a definition alone earns little. A workshop scheduler and a target-total search give students something to follow, and a trace table records the calls, the dead ends and the returns rather than just the final result. Students will: - describe the choice points, constraint tests and dead ends in a search - complete a trace table of calls and returns for a backtracking search - explain where a search resumes once a branch breaks a constraint - justify why the candidate value increases on both the include and the exclude route - set out the stored state, the constraint test and what is undone when a room allocation fails Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 2 written answers and 1 trace table. 18 marks, about 25 to 35 minutes. Series: H446 2.2.2 · Computational methods, part 4 of 14.
WorksheetOCR H446 2.2.2 Divide and conquer
Part 3 · H446 2.2.2 · Computational methods
Divide and conquer appears in H446 2.2.2 as a method with three named stages, and students can usually list them without being able to trace one. Starting from summing a list, this worksheet builds the divide, solve and combine shape, then asks for a working recursive implementation and a judgement about when a loop would serve better. Students will: - identify the divide, solve and combine stages in a described method - trace recursive calls as a tree and write each returned subtotal back upwards - explain why a call waits rather than disappearing while its children run - implement a recursive method that preserves the original list, handles an empty list and always uses a smaller slice - weigh a recursive design against a loop for very large inputs on a single processor Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 1 written answer and 2 Python tasks. 20 marks, about 25 to 35 minutes. Series: H446 2.2.2 · Computational methods, part 3 of 14.
WorksheetOCR H446 2.2.2 Decomposition and abstraction in solution design
Part 2 · H446 2.2.2 · Computational methods
Decomposition and abstraction are the paired design decisions H446 2.2.2 expects students to link, yet they are often answered with boxes on a diagram and nothing more. Here a venue-booking service is split into coherent responsibilities and students must state exactly what crosses each boundary and what a component should never need to know. Students will: - separate a mixed problem into components with coherent, distinct responsibilities - specify the data received, the rule applied and the result returned for a named component - name a detail a component should not need, and justify leaving it out - explain how decomposition and abstraction support each other rather than being alternatives - discuss problem recognition, decomposition and abstraction together against an unfamiliar library system Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 23 marks, about 20 to 30 minutes. Series: H446 2.2.2 · Computational methods, part 2 of 14.
WorksheetOCR H446 2.2.2 Computational solvability and problem recognition
Part 1 · H446 2.2.2 · Computational methods
OCR H446 2.2.2 begins with a question students often skip: can this problem be solved computationally at all? Working from a rehearsal-room allocation request, the worksheet teaches them to turn a vague human aim into precise inputs, rules, stored state and testable outputs before any algorithm is chosen. Students will: - identify the inputs, rules, stored state and outputs hidden inside a described need - rewrite an ambiguous requirement so that a program could execute and test it - explain why naming sequence, selection and iteration does not answer a question about computational methods - judge whether a loosely worded request is solvable as stated, and say what information would make part of it computable - recall the central distinctions from memory in a closed-book check Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 20 marks, about 20 to 30 minutes. Series: H446 2.2.2 · Computational methods, part 1 of 14.
WorksheetOCR H446 2.2.1 Paper 2 scenario exam transition
Part 14 · H446 2.2.1 · Programming techniques
An assessment piece rather than a teaching one, written as a single linked Paper 2 scenario that covers H446 2.2.1 end to end. A timed route event carries object modelling, OCR exam reference language, tracing, parameter modes, scope, recursion, debugging and evaluation, so it serves as a mock section or a final check before the topic is left behind. Students will: - derive attributes, methods and class relationships from an extended written scenario - write constructors, accessor methods and instantiation statements in OCR exam reference language - trace an algorithm and identify a range fault in a loop that totals a list - compare recursive traversal with iterative traversal using an explicit stack and recommend one - evaluate a stored running total against a calculated one and reach a justified conclusion Inside: 2 explanation cells, 1 multiple-choice question, 11 written answers and 1 trace table. 44 marks, about 70 to 85 minutes. Series: H446 2.2.1 · Programming techniques, part 14 of 14.
WorksheetOCR H446 2.2.1 Programming techniques consolidation
Part 13 · H446 2.2.1 · Programming techniques
Consolidation across the whole of H446 2.2.1, built on a hack-day dashboard that mixes control flow, recursion, scope, parameter modes, debugging and object orientation. No new content is introduced, so the demand is selecting the right technique and supporting each explanation with evidence, with the planning support withdrawn as students work through it. Students will: - select an appropriate technique for a task and state a one-line plan for it - trace a recursive function and the value it returns - identify a range fault in a loop header, explain its effect and correct it - implement a class combining stored state, a calculation and a decision - justify an object-oriented design in which polymorphism produces type-specific output Inside: 4 explanation cells, 1 multiple-choice question, 3 written answers, 1 Python task and 1 trace table. 19 marks, about 25 to 40 minutes. Series: H446 2.2.1 · Programming techniques, part 13 of 14.
WorksheetOCR H446 2.2.1 Object-oriented scenario solution
Part 12 · H446 2.2.1 · Programming techniques
By this point in H446 2.2.1 the object model has to come from prose rather than from a supplied diagram. An esports league scenario carries enough facts to derive Team and Match, so students justify what each class owns, implement result state that stays inside each object, then coordinate two collaborating objects. Students will: - derive classes, attributes and methods from a written scenario - state the relationship between two collaborating classes and defend it - implement a class whose result state is independent of other instances - write a class that stores and coordinates two objects of another class - explain why containment suits this design better than inheritance Inside: 8 explanation cells, 1 fill-in-the-blanks cell, 2 written answers and 2 Python tasks. 25 marks, about 30 to 45 minutes. Series: H446 2.2.1 · Programming techniques, part 12 of 14.
WorksheetOCR H446 2.2.1 Inheritance and polymorphism
Part 11 · H446 2.2.1 · Programming techniques
Not every relationship deserves inheritance, and H446 2.2.1 expects that test to be applied before a hierarchy is written. A digital exhibition with image and audio exhibits supplies shared identity and type-specific behaviour, so overriding and a single polymorphic call can be traced first and then built. Students will: - test whether a relationship is genuinely is-a rather than containment - reuse the parent constructor when initialising a child class - override an inherited method so one common call gives type-specific results - predict the output of a loop over a mixed list of related objects - explain how the type of the object decides which method runs Inside: 6 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 1 written answer and 2 Python tasks. 17 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 11 of 14.
WorksheetOCR H446 2.2.1 Encapsulation and getters/setters
Part 10 · H446 2.2.1 · Programming techniques
Encapsulation is easiest to explain through a rule that has to hold, so this H446 2.2.1 worksheet fixes a check-in score to the range 1 to 5 and asks what keeps it there. Students correct the getter and setter faults that recur in exam answers, then implement validated access that refuses an out-of-range update. Students will: - explain encapsulation in terms of a rule the object must keep true - recognise why a getter that does not return a value fails as a function - rewrite a getter and setter in OCR exam reference language with a proper parameter and return - implement a setter that validates its input and leaves state unchanged when it refuses - explain how controlled access reduces coupling to a class's internal representation Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 1 Python task. 19 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 10 of 14.
WorksheetOCR H446 2.2.1 Classes, objects and constructors
Part 9 · H446 2.2.1 · Programming techniques
Object orientation enters H446 2.2.1 with a small set of ideas that must be kept apart: class, object, attribute, method and constructor. A loan and event-pass context is used here so students see one definition producing several objects that each hold independent state, expressed in Python and in OCR exam reference language. Students will: - distinguish a class definition from an object created from it - identify what a constructor is responsible for alongside attributes and methods - read a class diagram and implement the class it describes - predict output that depends on two objects holding separate state - instantiate several objects and call a method on one without affecting the others Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 2 Python tasks. 19 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 9 of 14.
WorksheetOCR H446 2.2.1 IDE development and debugging
Part 8 · H446 2.2.1 · Programming techniques
Naming IDE features earns little on its own; H446 2.2.1 rewards linking a feature to the evidence it produces. A podcast queue that drops its final episode drives a reproduce, predict, inspect, repair and retest routine, so breakpoints, watches and tests are each used for a stated purpose. Students will: - distinguish syntax, runtime and logic errors from the behaviour observed - choose a breakpoint position and name the values worth watching there - explain what a variable watch shows that a passing or failing test does not - repair a loop so it processes every item, including empty and one-item lists - describe an investigation order that confirms a fault before any code is changed Inside: 7 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 2 written answers and 2 Python tasks. 16 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 8 of 14.
WorksheetOCR H446 2.2.1 Passing parameters by value and reference
Part 7 · H446 2.2.1 · Programming techniques
Whether a change survives a call depends on the parameter mode, and H446 2.2.1 examines that distinction directly. Two storage models are set side by side in this worksheet, a copy for pass by value and shared access for pass by reference, then applied to OCR exam reference language headers and to Python's own behaviour. Students will: - model caller and callee storage separately for a single call - trace a procedure whose scalar parameter is passed by value - explain how the same procedure behaves differently under pass by reference - write an OCR exam reference language header that mixes both parameter modes - recommend a parameter mode for a shared variable and state a risk it introduces Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 4 written answers and 1 trace table. 19 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 7 of 14.
WorksheetOCR H446 2.2.1 Modularity, functions and procedures
Part 6 · H446 2.2.1 · Programming techniques
H446 2.2.1 treats modularity as design, not simply as splitting code up. A sports-results service is decomposed here into validation, calculation and display, so each subprogram carries one responsibility and a stated interface, and students can defend the split using OCR's function and procedure terminology. Students will: - decompose a longer program into subprograms with coherent responsibilities - state the inputs, returned values and side effects of each subprogram - distinguish a function from a procedure as OCR defines them - implement a calculating function and a display subprogram with clear interfaces - explain how the decomposition improves both testing and maintenance Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 3 written answers and 2 Python tasks. 23 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 6 of 14.
WorksheetOCR H446 2.2.1 Variable scope
Part 5 · H446 2.2.1 · Programming techniques
Two variables can share a name and still be separate storage, which is where H446 2.2.1 scope questions usually turn. Using a live-stream overlay, this worksheet has students read names from the inside out, predict shadowing without running the code, then replace global state with an explicit parameter and return interface. Students will: - identify which local and global bindings are accessible at a given point - predict the output of a program where a local name shadows a global one - explain the difference between a global and a local variable of the same name - refactor a function to receive state as parameters and return the updated value - explain drawbacks of relying heavily on global variables in a larger program Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 2 Python tasks. 15 marks, about 20 to 30 minutes. Series: H446 2.2.1 · Programming techniques, part 5 of 14.
WorksheetOCR H446 2.2.1 Recursion and iteration compared
Part 4 · H446 2.2.1 · Programming techniques
Once students can write both forms, H446 2.2.1 asks them to choose between them. Recursion and iteration are compared here on shared criteria, clarity and memory cost, with translation in both directions so the comparison rests on genuinely equivalent code rather than on preference. Students will: - map base cases, recursive parameters and returns onto their iterative equivalents - explain why an iterative version may use less additional memory on a long list - compare two supplied functions using clarity and overhead as common criteria - convert an iterative routine into a recursive one that returns the same list - recommend an approach for a nested structure of varying depth and state one trade-off Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 3 Python tasks. 20 marks, about 30 to 40 minutes. Series: H446 2.2.1 · Programming techniques, part 4 of 14.
WorksheetOCR H446 2.2.1 Recursive functions
Part 3 · H446 2.2.1 · Programming techniques
Recursion is examined in H446 2.2.1 as a tracing skill and a construction skill at once. This worksheet separates the two directions of a recursive call, the descent into smaller problems and the unwinding of returned values, so students can explain why a function terminates rather than only recognise the pattern. Students will: - distinguish the base case from the recursive case in a supplied function - trace recursive calls alongside the values returned as they unwind - explain termination and the order in which results are combined - write a recursive digit sum using remainder and integer division - repair a recursion that never reaches a base case and justify the repair Inside: 6 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 2 written answers, 1 Python task and 1 trace table. 18 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 3 of 14.
WorksheetOCR H446 2.2.1 Tracing and debugging control flow
Part 2 · H446 2.2.1 · Programming techniques
Faults that appear only at particular input sizes are the ones students find hardest to explain. Sitting in H446 2.2.1, this worksheet turns execution into visible state, so students trace combined control flow, name the observable effect of an off-by-one condition and prove a repair with boundary tests. Students will: - construct a trace of combined selection and iteration in execution order - recognise an off-by-one fault in a Python range and state what it causes - identify a faulty boundary condition, explain its effect and give a corrected version - repair a counting function so it terminates with the required result - write a fresh algorithm to a stated specification and justify the test values chosen Inside: 8 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers, 3 Python tasks and 1 trace table. 19 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 2 of 14.
WorksheetOCR H446 2.2.1 Control structures in OCR and Python
Part 1 · H446 2.2.1 · Programming techniques
OCR H446 2.2.1 expects students to move between OCR's exam reference language and Python, where the same loop can carry different boundaries. This worksheet builds the sequence, selection and iteration model first, makes the FOR and range boundary difference explicit, then asks students to construct control flow from a stated requirement. Students will: - identify sequence, selection and iteration in a described requirement - translate OCR exam reference language loop boundaries into the equivalent Python range - trace a timetable algorithm and record how its state changes on each pass - write Python selection that assigns values across several discrete cases - recommend a loop type when the number of attempts is not known in advance and justify it Inside: 7 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 2 written answers, 2 Python tasks and 1 trace table. 16 marks, about 25 to 35 minutes. Series: H446 2.2.1 · Programming techniques, part 1 of 14.
WorksheetOCR H446 2.1.5 Thinking concurrently
Part 1 · H446 2.1.5 · Thinking concurrently
Concurrency in OCR H446 2.1.5 is judged by dependencies and shared state rather than by speed alone. A live youth-media broadcast lets students decide what can safely overlap, what must wait for data, and what a single shared status flag can hide. Students will: - distinguish tasks that may overlap from tasks tied together by a data dependency - justify a pair of broadcast tasks that must stay in strict order - explain how two tasks writing one shared status value cause premature publishing - describe a separate-flag design that prevents that failure - evaluate concurrent processing with benefits, trade-offs and a justified conclusion Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 25 marks, about 25 to 35 minutes. Series: H446 2.1.5 · Thinking concurrently, part 1 of 1.
WorksheetOCR H446 2.1.4 Decisions, logical conditions and flow
Part 1 · H446 2.1.4 · Thinking logically
OCR H446 2.1.4 is about decisions that change the route through a solution, and about the boundary values where those decisions quietly go wrong. A community makerspace access policy gives students conditions to write, trace, repair and then extend. Students will: - identify a genuine decision point and the condition that controls it - write a Boolean condition combining membership, training and an age threshold - repair a comparison operator that fails only at the boundary value - trace nested decisions and explain why one route is never reached - implement the access routes in Python and extend the rule with an alternative condition Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 3 written answers, 1 Python task and 1 trace table. 19 marks, about 25 to 35 minutes. Series: H446 2.1.4 · Thinking logically, part 1 of 1.
WorksheetOCR H446 2.1.3 Procedural order and sub-procedures
Part 2 · H446 2.1.3 · Thinking procedurally
Correct components in the wrong order still produce an incorrect solution, which is the reasoning OCR H446 2.1.3 examines here. A digital escape-room booking workflow drives the ordering work, supported by a trace table, a Python admission function and a pseudocode design task. Students will: - order sub-procedures using data dependencies, preconditions and state changes - explain why validation must come before any change to stored capacity - trace a workflow and record which route reaches confirmation - implement an ordered admission function that leaves external state unchanged - design pseudocode from named sub-procedures showing parameters and returned values Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 2 written answers, 1 Python task and 1 trace table. 22 marks, about 25 to 35 minutes. Series: H446 2.1.3 · Thinking procedurally, part 2 of 2.
WorksheetOCR H446 2.1.3 Decomposition and solution components
Part 1 · H446 2.1.3 · Thinking procedurally
Thinking procedurally, OCR H446 2.1.3, starts with breaking a system apart along defensible lines. A student-run festival system and a community equipment-loan service give students practice at giving every component one responsibility and a clear interface. Students will: - distinguish the components of a problem from the components of a solution - give each component a single responsibility with named inputs and outputs - explain the problems caused by one component doing several unrelated jobs - propose better boundaries to replace an overloaded component - decompose an unfamiliar system and state a testing or teamwork benefit that follows Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 3 written answers. 22 marks, about 25 to 35 minutes. Series: H446 2.1.3 · Thinking procedurally, part 1 of 2.
WorksheetOCR H446 2.1.2 Program caching and reusable components
Part 2 · H446 2.1.2 · Thinking ahead
Caching and reusable components are the two thinking-ahead mechanisms named in OCR H446 2.1.2, and both fail when validity or the interface is left vague. Students trace hits and misses in a live-event app, judge a 24 hour cache policy against changing closures, and write a reusable duration formatter in Python. Students will: - trace a cache hit and a cache miss and say what is computed or stored in each - separate a program cache designed in application code from hardware processor cache - explain how a stale cached result arises and recommend a better policy - implement a small reusable function that honours a stated precondition - justify reusing a component and state one check to make before adopting it Inside: 8 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 2 written answers and 2 Python tasks. 23 marks, about 30 to 40 minutes. Series: H446 2.1.2 · Thinking ahead, part 2 of 2.
WorksheetOCR H446 2.1.2 Inputs, outputs and preconditions
Part 1 · H446 2.1.2 · Thinking ahead
Thinking ahead in OCR H446 2.1.2 begins with knowing exactly what data arrives, what leaves and what must already be true. A pop-up concert service and an accessible-seating allocator push students past naming input devices towards qualified data items and stated preconditions. Students will: - identify input and output data together with its meaning and format - distinguish input data from the device that captures it - state the preconditions that must hold before a process can run correctly - read the inputs, output and preconditions out of a short pseudocode function - specify a full data contract for a step-free seat allocation service Inside: 8 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 25 marks, about 25 to 35 minutes. Series: H446 2.1.2 · Thinking ahead, part 1 of 2.
WorksheetOCR H446 2.1.1 Devising and evaluating abstract models
Part 2 · H446 2.1.1 · Thinking abstractly
Beyond selecting detail, OCR H446 2.1.1 asks students to devise abstract models and then judge them. Racing-game opponents, two journey-time models and a venue queue make the model boundary and its assumptions the thing under evaluation. Students will: - state the entities, properties and rules a model needs to meet its purpose - draw a model boundary and say what is deliberately left outside it - tell a limitation of a model apart from a fault in its code - compare two models on data required, processing complexity and likely accuracy, then recommend one - devise a queue model and state the limitation its assumptions create Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 3 written answers. 25 marks, about 25 to 35 minutes. Series: H446 2.1.1 · Thinking abstractly, part 2 of 2.
WorksheetOCR H446 2.1.1 Thinking abstractly: purpose and relevant detail
Part 1 · H446 2.1.1 · Thinking abstractly
OCR H446 2.1.1 treats abstraction as a purposeful filter, not simply as making something smaller. Starting from a city cycling map and ending with an event map that must serve step-free routes, this worksheet has students decide what to keep and what to leave out from a stated purpose. Students will: - define abstraction in terms of the purpose a model has to serve - decide which details to retain and which to suppress for a named user decision - explain a benefit of abstraction when developing a real system - repair a weak model with one justified removal and one justified addition - devise a model for a new context and justify an inclusion and an exclusion Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 22 marks, about 25 to 35 minutes. Series: H446 2.1.1 · Thinking abstractly, part 1 of 2.
WorksheetOCR H446 2.1 Choosing and applying computational-thinking approaches
Part 2 · H446 2.1 · Elements of computational thinking
Before the assessment, students need to pick the right mode rather than recite five definitions. This consolidation worksheet for OCR H446 2.1 sorts problems by their central decision, repairs the misconceptions that cost the most marks, and applies all five modes to a council water-refill station app. Students will: - choose the computational-thinking mode that a problem's central decision calls for - correct common misconceptions about abstraction and about concurrent execution - map all five modes onto one system and explain a connection between two of them - trace a recommendation and explain why its result stays False - decide which tasks may overlap and what must hold before an update is published Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 4 written answers and 1 trace table. 36 marks, about 30 to 45 minutes. Series: H446 2.1 · Elements of computational thinking, part 2 of 2.
WorksheetOCR H446 2.1 Integrated computational-thinking exam transition
Part 1 · H446 2.1 · Elements of computational thinking
The assessment for the whole of OCR H446 2.1: one city arts-trail app, and all five computational-thinking modes examined inside it, from inputs and abstraction through caching, reuse, decomposition, ordering, decisions and concurrency. Students work closed-book, with correctness held until teacher review. Students will: - select and apply the right computational-thinking mode without being told which it is - specify inputs, outputs and missing preconditions for an unfamiliar service - devise an abstraction and state the limitation its omissions create - evaluate a cache policy and a component-reuse decision in the same system - decompose the system, order its sub-procedures and judge which work may overlap Inside: 2 explanation cells, 1 multiple-choice question, 11 written answers and 1 trace table. 54 marks, about 70 to 85 minutes. Series: H446 2.1 · Elements of computational thinking, part 1 of 2.
WorksheetOCR H446 1.5.2 Moral, social, ethical and cultural exam transition
Part 9 · H446 1.5.2 · Moral and ethical issues
This is a selectable assessment bank for OCR H446 1.5.2 rather than one compulsory 54-mark sitting. Teachers can set the five-mark retrieval check followed by a section on work and automated decisions, environment and control of information, or personal information, communication and culture. Objective feedback is held for teacher review. Students will: - complete a short retrieval check before the section or sections set by the teacher - select relevant issues from exact facts in an unfamiliar scenario - explain effects on particular people or groups and consider another viewpoint - keep permission, harm, legality and morality as four separate claims - reach a supported conclusion when the command word requires one Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 7 written answers. 54 marks, about 20 to 40 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 9 of 9.
WorksheetOCR H446 1.5.2 Moral, social, ethical and cultural mastery and transfer
Part 8 · H446 1.5.2 · Moral and ethical issues
A consolidation task that pulls the whole of OCR H446 1.5.2 together: stakeholders, environment, monitoring, inference, permission, communication and culture, all applied to systems students have not met before. It begins closed-book and introduces no new content, so it sits as the rehearsal directly before the exam-transition paper. Students will: - select the issues a scenario genuinely raises instead of listing every possible one - use an exact scenario fact to explain an effect on a particular person or group - explain which concerns a redesigned system removes and which it leaves untouched - consider another viewpoint or safeguard where the question requires it - plan developed points for an unfamiliar 1.5.2 discussion question Inside: 5 explanation cells, 2 fill-in-the-blanks cells and 4 written answers. 36 marks, about 40 to 60 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 8 of 9.
WorksheetOCR H446 1.5.2 Cultural interface design
Part 7 · H446 1.5.2 · Moral and ethical issues
OCR H446 1.5.2 names layout, colour paradigms and character sets, so general accessibility points will not earn the cultural marks. Through an international appointment app and a global emergency app, students see exactly what breaks when an interface is translated but not localised. Students will: - explain why reversing reading order changes navigation order and icon direction - identify a character-set failure and the specific change that fixes it - describe how colour meaning varies between audiences and why colour alone is unsafe - diagnose several distinct cultural failures in one interface and improve each - recommend a localisation process that includes testing with the intended users Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 27 marks, about 30 to 50 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 7 of 9.
WorksheetOCR H446 1.5.2 Piracy and offensive communication
Part 6 · H446 1.5.2 · Moral and ethical issues
Copying without permission and communicating harm are different wrongs, and OCR H446 1.5.2 answers lose marks when the two are merged. This worksheet keeps them apart as separate tests, then asks students to support legal and moral conclusions with their own distinct evidence. Students will: - distinguish a question of permission to copy from a question of harmful communication - explain why a small private audience does not create permission - show why permission to use material does not excuse the message attached to it - analyse how one incident affects a creator, users, a platform and public discussion differently - evaluate an automatic blocking proposal and recommend a better approach Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 20 to 40 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 6 of 9.
WorksheetOCR H446 1.5.2 Analysing and monitoring personal information
Part 5 · H446 1.5.2 · Moral and ethical issues
In the monitoring scenarios of OCR H446 1.5.2, the harm usually begins at analysis rather than at collection. Students follow personal data from collection through combination and inference to a decision and its consequence, using insurance pricing, a learning platform's effort label and shopping-centre tracking. Students will: - trace personal data from what was collected to the decision it eventually produces - explain how accurate raw data can still support an unfair inference - judge whether a person would expect, notice or be able to challenge a use of their data - propose safeguards covering accuracy, purpose and a practical route of appeal - discuss the implications of combining several tracking sources in one public space Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 30 to 50 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 5 of 9.
WorksheetOCR H446 1.5.2 Censorship, monitoring and the Internet
Part 4 · H446 1.5.2 · Moral and ethical issues
Blocking content can protect people and can silence them, often by the same mechanism. Covering OCR H446 1.5.2, this worksheet has students evaluate censorship and monitoring by asking who controls information, for what purpose, by what means and with which safeguards, across a school discussion board, remote-staff monitoring and emergency health moderation. Students will: - describe the mechanism by which content is controlled and who sets the rules - separate a protective aim from its effect on lawful expression - explain how narrow rules, notification and appeal reduce over-blocking - evaluate workplace monitoring in terms of benefit, risk and proportionate safeguard - recommend a moderation policy and justify it against the competing interests Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 30 to 50 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 4 of 9.
WorksheetOCR H446 1.5.2 Environmental lifecycle of computing
Part 3 · H446 1.5.2 · Moral and ethical issues
Environmental questions in OCR H446 1.5.2 are too often answered with electricity use alone. This worksheet extends the analysis across extraction, manufacture, transport, use, repair and disposal, then puts students inside a replace-or-extend decision about school hardware. Students will: - describe the environmental effects that arise at each stage of a device lifecycle - distinguish impacts created during manufacture from those created while a device is in use - weigh remaining life and repairability against the efficiency of a replacement - suggest design changes that reduce the impact of a streaming service without assuming it stops - state the evidence that should decide a hardware replacement recommendation Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 20 to 40 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 3 of 9.
WorksheetOCR H446 1.5.2 Automated decisions, AI and bias
Part 2 · H446 1.5.2 · Moral and ethical issues
Bias in an automated decision needs a cause, an outcome and a response. Written for OCR H446 1.5.2, this worksheet follows data into a ranking decision and back through a feedback loop, using apprenticeship shortlisting, hospital prioritisation and AI-set credit limits as its contexts. Students will: - locate the points at which bias enters an automated decision system - explain how an unequal outcome feeds back into future training data - describe a test that would show whether a ranking model produces unequal outcomes - propose mitigations that address the cause of a bias rather than its symptom - discuss the implications of an AI credit decision for customers, the lender and communities Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 30 to 50 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 2 of 9.
WorksheetOCR H446 1.5.2 Workforce and effects on different groups
Part 1 · H446 1.5.2 · Moral and ethical issues
OCR H446 1.5.2 rewards answers that trace how a system change reaches particular people, not broad claims that automation removes jobs. Using automated warehouse scheduling and bus dispatch, students identify the task that changes, explain the effects on different groups and judge how the change should be introduced. Students will: - identify the task changed by an automated system before explaining its effects - identify the distinct stakeholder groups affected by one workforce change - explain an opportunity and a risk for the same group without treating them as opposites - discuss the effects of an automated public service on workers, users and the wider community - recommend how a workforce change should be introduced and justify that recommendation Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 20 to 40 minutes. Series: H446 1.5.2 · Moral and ethical issues, part 1 of 9.
WorksheetOCR H446 1.5.1 Computing-related Legislation examination transition
Part 5 · H446 1.5.1 · Computing related legislation
Best used as a closed-book assessment once the rest of the series is complete, this paper covers OCR H446 1.5.1 with the teaching support removed. Its questions run from principle application and law selection to an extended evaluation of surveillance powers and the difference between what is unethical and what is unlawful. Students will: - apply named data-protection principles to a described record-keeping context - explain how the Computer Misuse Act applies when authorisation is exceeded - identify a copyright problem and give one lawful route to using the work - evaluate a proposed use of investigatory powers at extended-answer length - argue why unethical and illegal are not interchangeable, using a case from the paper Inside: 2 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 7 written answers. 55 marks, about 65 to 80 minutes. Series: H446 1.5.1 · Computing related legislation, part 5 of 5.
WorksheetOCR H446 1.5.1 Legislation mastery and transfer
Part 4 · H446 1.5.1 · Computing related legislation
Real situations rarely engage a single law, and OCR H446 1.5.1 rewards students who keep separate actions as separate chains of reasoning. This consolidation worksheet puts data protection, computer misuse, copyright and investigatory powers into multi-action scenarios and drills one response structure: the fact, the Act, the action or principle it engages, then the consequence. Students will: - select the most directly relevant law for each fact in a mixed list - analyse one scenario in which three different laws may each apply - explain why a licence does not make an unlawful acquisition lawful - distinguish the problems that changed facts remove from those that remain - set out a repeatable method for choosing legislation in an unfamiliar scenario Inside: 5 explanation cells, 2 fill-in-the-blanks cells and 6 written answers. 47 marks, about 55 to 70 minutes. Series: H446 1.5.1 · Computing related legislation, part 4 of 5.
WorksheetOCR H446 1.5.1 RIPA powers, purpose and proportionality
Part 3 · H446 1.5.1 · Computing related legislation
The Regulation of Investigatory Powers Act 2000 is assessed in OCR H446 1.5.1 as both a source of authorised powers and a source of privacy concerns, so a one-sided answer cannot reach the higher marks. This worksheet builds the whole chain, from an authorised body and a legitimate purpose through to necessity, proportionality and safeguards. Students will: - link an authorised public body and a stated purpose to one specific covert power - weigh an investigative benefit against the privacy cost to the people affected - judge whether a proposed use is necessary and proportionate, or whether a narrower option exists - repair a one-sided response that names a power without a purpose or a limit - produce a balanced evaluation of a serious case that includes safeguards Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 36 marks, about 45 to 60 minutes. Series: H446 1.5.1 · Computing related legislation, part 3 of 5.
WorksheetOCR H446 1.5.1 Computer misuse and copyright boundaries
Part 2 · H446 1.5.1 · Computing related legislation
Two laws, two different questions: OCR H446 1.5.1 expects students to test authorisation to access a system separately from permission to copy protected work. This worksheet teaches selection from the facts of a case, so that neither 'hacking' nor 'copyright' is used as a loose moral label. Students will: - decide which law an action engages from the access or copying fact that describes it - apply both laws to one scenario in which each covers a different action - explain how written authorisation or a licence changes the legal analysis - correct claims that treat being able to open a file as permission to use it - analyse a case in which an authorised user goes beyond what they may do Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 30 marks, about 45 to 60 minutes. Series: H446 1.5.1 · Computing related legislation, part 2 of 5.
WorksheetOCR H446 1.5.1 Data protection: exam model and current-law bridge
Part 1 · H446 1.5.1 · Computing related legislation
OCR H446 1.5.1 asks students to apply data-protection principles, but the specification still names the Data Protection Act 1998 while current UK practice runs on the 2018 Act and the UK GDPR. This worksheet teaches the examined model and makes that boundary explicit, so historical exam content is never presented as today's law. Students will: - apply the examined data-protection principles to a described processing activity - identify the processing action a principle engages, rather than naming the law alone - separate the examined 1998 naming from the current DPA 2018 and UK GDPR framework - correct a claim that treats the two layers as interchangeable - evaluate data-protection risks in an extended scenario and justify the principles engaged Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 28 marks, about 45 to 60 minutes. Series: H446 1.5.1 · Computing related legislation, part 1 of 5.
WorksheetOCR H446 1.4.3 Boolean algebra exam transition
Part 11 · H446 1.4.3 · Boolean algebra
This is an assessment piece rather than a teaching one, so it works best as a closed-book check after the rest of the OCR H446 1.4.3 series. Explanatory support is removed, and five examination-style questions run from scenario translation through truth table, named laws and a four-variable Karnaugh map to component comparison. Students will: - translate a multi-condition scenario into an expression and a circuit unaided - complete a truth-table output column in systematic input order - simplify an expression with named laws and a visible intermediate stage - annotate the optimal groups on a supplied map and state the simplified result - compare adder types and explain flip-flop clock behaviour in one extended answer Inside: 7 explanation cells, 1 fill-in-the-blanks cell and 4 written answers. 23 marks, about 60 to 75 minutes. Series: H446 1.4.3 · Boolean algebra, part 11 of 11.
WorksheetOCR H446 1.4.3 Boolean algebra consolidation
Part 10 · H446 1.4.3 · Boolean algebra
By this point students hold a series of separate techniques for OCR H446 1.4.3, and the examined difficulty shifts to choosing between them. This consolidation worksheet interleaves notation, circuits, truth tables, named laws, Karnaugh maps, adders and flip-flops, and closes with an error clinic built from mistakes OCR assessment repeatedly exposes. Students will: - choose the representation that suits the demand a question is making - simplify an expression with named laws in a mixed-topic set of tasks - populate and group a Karnaugh map without a nearby worked example to copy - identify which logic component fits a described job and justify the choice - check finished work against frequently reported errors before handing in Inside: 5 explanation cells, 2 multiple-choice questions, 3 fill-in-the-blanks cells and 3 written answers. 32 marks, about 55 to 70 minutes. Series: H446 1.4.3 · Boolean algebra, part 10 of 11.
WorksheetOCR H446 1.4.3 D-type flip-flops
Part 9 · H446 1.4.3 · Boolean algebra
Every other circuit in OCR H446 1.4.3 calculates an output from its current inputs; a D-type flip-flop stores one bit over time. This worksheet covers clock-edge sampling, the held output between edges, and, just as usefully for revision, where the required knowledge stops. Students will: - explain that the output copies the D input only at an active clock edge - state what the output does when D changes between two edges - describe how several flip-flops together hold a multi-bit value in a register - compare a circuit that stores state with one that only combines current inputs - recognise which electronics detail sits outside the required H446 knowledge Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 2 written answers. 19 marks, about 35 to 45 minutes. Series: H446 1.4.3 · Boolean algebra, part 9 of 11.
WorksheetOCR H446 1.4.3 Half and full adders
Part 8 · H446 1.4.3 · Boolean algebra
Adders are where Boolean algebra turns into arithmetic, and OCR H446 1.4.3 asks students to construct a full adder from correctly connected stages rather than recall a picture of one. This worksheet separates the jobs of the Sum and Carry outputs, then wires two half-adder stages together with the carry path made explicit. Students will: - state the Sum and Carry outputs of a half adder for each pair of input bits - describe the differences between a half adder and a full adder - follow a carry-in through two XOR, two AND and one OR gate - work out full-adder outputs for given inputs including an incoming carry - draw and label a complete full-adder circuit Inside: 5 explanation cells, 2 multiple-choice questions, 3 fill-in-the-blanks cells and 2 written answers. 21 marks, about 45 to 55 minutes. Series: H446 1.4.3 · Boolean algebra, part 8 of 11.
WorksheetOCR H446 1.4.3 Four-variable Karnaugh maps
Part 7 · H446 1.4.3 · Boolean algebra
With 16 input states, grouping has to become a reliable routine rather than an intuition. Pitched at OCR H446 1.4.3, this worksheet sets out a step-by-step grouping procedure, works a wraparound pair on a full four by four map, and insists on the visible annotation that examination questions ask for. Students will: - transfer a truth-table row to the correct cell of a four-variable map - work out how many cells a term makes true when some variables are absent - follow a fixed routine that covers every 1 with the fewest, largest groups - reject a proposed group that contains a 0 or breaks the power-of-two rule - annotate a map with its groups and write the simplified expression Inside: 10 explanation cells, 6 multiple-choice questions, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 50 to 60 minutes. Series: H446 1.4.3 · Boolean algebra, part 7 of 11.
WorksheetOCR H446 1.4.3 Three-variable Karnaugh maps
Part 6 · H446 1.4.3 · Boolean algebra
Eight input states, Gray-code column order and wraparound adjacency are what make three-variable maps harder than two, and OCR H446 1.4.3 expects all three. This worksheet decodes a cell before anything is placed in it, then builds towards overlapping and edge-wrapping groups. Students will: - combine a column heading and a row heading to recover a complete three-variable state - explain why the headings run 00, 01, 11, 10 rather than in binary counting order - place an expression on a map term by term, treating absent variables correctly - form the largest legal groups, including a group that wraps across the edge - justify why a single 1 may belong to more than one group Inside: 8 explanation cells, 5 multiple-choice questions, 3 fill-in-the-blanks cells and 1 written answer. 30 marks, about 45 to 55 minutes. Series: H446 1.4.3 · Boolean algebra, part 6 of 11.
WorksheetOCR H446 1.4.3 Two-variable Karnaugh maps
Part 5 · H446 1.4.3 · Boolean algebra
A Karnaugh map is a truth table rearranged as a grid, and students who never learn which cell holds which input state go wrong before any grouping begins. Covering OCR H446 1.4.3, this worksheet builds the two-variable map from locating a state, through placing outputs, to reading a term from a group. Students will: - locate the cell that represents a given input state - transfer truth-table or expression outputs into the correct map cells - decide whether a proposed group is valid in size and shape - read a term from a group by asking which variables stay constant - explain why a diagonal pair of cells cannot be treated as adjacent Inside: 8 explanation cells, 4 multiple-choice questions, 2 fill-in-the-blanks cells and 2 written answers. 19 marks, about 40 to 50 minutes. Series: H446 1.4.3 · Boolean algebra, part 5 of 11.
WorksheetOCR H446 1.4.3 Boolean laws and simplification
Part 4 · H446 1.4.3 · Boolean algebra
Simplification earns marks for the stages shown, not only the final line, and OCR H446 1.4.3 names rule families that students must apply by name. This worksheet works through commutation, association, distribution, absorption and De Morgan's laws with every intermediate transformation visible. Students will: - name the law that justifies a given transformation - apply De Morgan's laws so the operator switches as well as the terms - distribute a repeated term without losing the operator that joins the brackets - simplify an expression stage by stage, naming the law used at each step - explain the practical hardware benefits of using fewer gates Inside: 6 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 2 written answers. 18 marks, about 45 to 55 minutes. Series: H446 1.4.3 · Boolean algebra, part 4 of 11.
WorksheetOCR H446 1.4.3 Circuits, expressions and truth tables
Part 3 · H446 1.4.3 · Boolean algebra
Moving in any direction between scenario, expression, circuit and truth table is the central demand of OCR H446 1.4.3, and it is where bracket errors surface. This worksheet drills all four representations together, including reading an expression back off a circuit by starting at the final gate. Students will: - complete a full truth table using systematic input ordering - write an expression from a circuit by working backwards from the final gate - draw a labelled circuit from a given expression while preserving grouping - match a Boolean expression to the circuit that produces it - work out how many rows a complete truth table needs for a defined set of variables Inside: 6 explanation cells, 2 multiple-choice questions, 3 fill-in-the-blanks cells and 2 written answers. 28 marks, about 45 to 55 minutes. Series: H446 1.4.3 · Boolean algebra, part 3 of 11.
WorksheetOCR H446 1.4.3 Logic gates and signal tracing
Part 2 · H446 1.4.3 · Boolean algebra
Reading a circuit is a separate skill from knowing what a gate does, and OCR H446 1.4.3 examines both. This worksheet covers the four required gate symbols and the discipline of tracing one signal at a time, including why a flowchart decision symbol never answers a logic-circuit question. Students will: - recognise the OCR symbols for AND, OR, NOT and XOR gates - name the intermediate signals between gates instead of jumping to the output - work out a circuit output for a given set of input values - explain what a small circle on a gate output indicates - predict how a circuit behaves when one of its gates is replaced Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 1 written answer. 15 marks, about 40 to 50 minutes. Series: H446 1.4.3 · Boolean algebra, part 2 of 11.
WorksheetOCR H446 1.4.3 Boolean logic and notation
Part 1 · H446 1.4.3 · Boolean algebra
OCR H446 1.4.3 opens with notation, and students who cannot turn a sentence into variables lose marks long before they reach a Karnaugh map. This first worksheet in the series builds that translation habit and separates AND, OR, NOT and XOR in the notation OCR uses. Students will: - represent two-state conditions as 0 and 1 using OCR operator symbols - distinguish an inclusive OR from an exclusive XOR in a described situation - define suitable variables for a written scenario before writing any expression - write a Boolean expression that keeps the scope of a negation correct - recall operator meanings without an answer bank in a closed-book check Inside: 6 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 1 written answer. 16 marks, about 35 to 45 minutes. Series: H446 1.4.3 · Boolean algebra, part 1 of 11.
WorksheetOCR H446 1.4.2 Data Structures exam transition
Part 14 · H446 1.4.2 · Data structures
The assessment piece for H446 1.4.2, worked independently and without checking answers along the way. An original community-transport scenario samples the whole specification point in one sitting, from structure selection and state tracing through to implementation reasoning and an evaluative recommendation, so it doubles as a readiness check before exam questions. Students will: - recommend structures for a record, a fixed two-dimensional plan and an editable ordered list, with justification - describe stack and circular queue state changes including pointers and returned values - give safe linked-list pointer updates and a binary search tree comparison path with its insertion point - explain search and safe removal for two colliding keys in a chained hash table - reach and justify a recommendation between a queue and a stack under a new demand Inside: 2 explanation cells, 1 multiple-choice question, 8 written answers and 1 trace table. 36 marks, about 70 to 85 minutes. Series: H446 1.4.2 · Data structures, part 14 of 14.
WorksheetOCR H446 1.4.2 Data Structures consolidation
Part 13 · H446 1.4.2 · Data structures
This is the mixed revision set for H446 1.4.2, so no new structures appear. Contexts are interleaved deliberately, which forces students to diagnose the behaviour a requirement needs before naming a structure, starting from a closed-book retrieval section and ending in an integrated game-server design. Students will: - recall structure choices from memory across contexts presented out of teaching order - diagnose the required behaviour, such as indexed shape or ordered removal, before choosing a structure - trace circular queue pointer updates and correct an unsafe linked-list insertion order - compare a directed graph with a tree, and a binary search tree with a hash table, for stated purposes - select and justify structures for six differing requirements in one game-server design Inside: 4 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 5 written answers and 1 trace table. 35 marks, about 60 to 75 minutes. Series: H446 1.4.2 · Data structures, part 13 of 14.
WorksheetOCR H446 1.4.2 Integrated data-structure implementation
Part 12 · H446 1.4.2 · Data structures
Most of H446 1.4.2 is taught one structure at a time, but questions combine them. A community-media studio that lends equipment and schedules editing jobs makes students select records, a queue and a hash table together, define the interfaces first, and only then write the code behind them. Students will: - map the operations a scenario requires onto the behaviour of candidate structures - justify a combination of records, a queue and a hash table, rejecting one plausible alternative - define function interfaces before implementing anything behind them - implement a first in, first out job queue and build a register keyed by item ID with a stated duplicate policy - evaluate removing from the front of a Python list against a circular array or linked queue at scale Inside: 8 explanation cells, 1 fill-in-the-blanks cell, 2 written answers and 2 Python tasks. 26 marks, about 55 to 70 minutes. Series: H446 1.4.2 · Data structures, part 12 of 14.
WorksheetOCR H446 1.4.2 Hash tables and collisions
Part 11 · H446 1.4.2 · Data structures
Hash tables buy fast lookup from a key, provided the collision policy is declared and then followed consistently. Set in a community equipment register, this H446 1.4.2 worksheet covers bucket calculation, chaining and linear probing, and draws the boundary between a hash table's bucket function and the cryptographic hashing of a password. Students will: - apply a simple modulo hash function to place keys into buckets - resolve collisions under a declared policy such as separate chaining or linear probing - implement lookup, insertion, update and removal for a chained table - separate a bucket function from a password hash despite the shared terminology - explain how table size and frequent collisions affect lookup performance Inside: 9 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 3 written answers and 2 Python tasks. 32 marks, about 45 to 55 minutes. Series: H446 1.4.2 · Data structures, part 11 of 14.
WorksheetOCR H446 1.4.2 Binary search trees: operations
Part 10 · H446 1.4.2 · Data structures
The binary search tree in H446 1.4.2 is where ordering becomes an operation: each comparison discards a whole subtree. This worksheet works through search, insertion, the three deletion cases and the depth-first traversal orders, and closes on why the shape of the tree, not just its contents, decides how well search performs. Students will: - apply the ordering invariant across a whole subtree rather than to one parent comparison - search for and insert values by repeated comparison, giving the comparison path taken - handle removal of leaf, one-child and two-child nodes consistently - give pre-order, in-order and post-order traversals and say which produces sorted output - explain how already sorted input can leave a tree behaving much like a linked list Inside: 10 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 3 written answers and 2 Python tasks. 33 marks, about 50 to 60 minutes. Series: H446 1.4.2 · Data structures, part 10 of 14.
WorksheetOCR H446 1.4.2 Trees and hierarchical structures
Part 9 · H446 1.4.2 · Data structures
A festival programme of categories and activities gives H446 1.4.2 tree vocabulary something concrete to describe. This worksheet holds students to exact terms for the parts of a tree, then makes the point that removing an internal node needs a stated policy, because the structure alone does not decide one. Students will: - use root, parent, child, sibling, leaf, subtree and depth accurately under a stated depth convention - distinguish binary from multi-branch trees and read child-pointer values including absent children - choose and state a removal policy for an internal node rather than assuming one - contrast breadth-first and depth-first traversal by the state each one keeps - design a media-library hierarchy and justify the tree type, one traversal purpose and one removal Inside: 7 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 24 marks, about 45 to 55 minutes. Series: H446 1.4.2 · Data structures, part 9 of 14.
WorksheetOCR H446 1.4.2 Graph creation and operations
Part 8 · H446 1.4.2 · Data structures
Reading a graph is one skill; changing one without leaving dangling references is another, and H446 1.4.2 examines both. Here a venue network gains and loses locations and routes, so students maintain an adjacency list through additions, removals and traversal of a graph that contains cycles. Students will: - create vertices and edges in an adjacency-list graph - add directed and undirected edges without creating duplicates - remove a vertex together with every edge that points at it - apply a sequence of changes and give the full adjacency list after each one - explain why traversal of a cyclic graph needs a visited set, and what reachable means Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 3 Python tasks. 22 marks, about 45 to 55 minutes. Series: H446 1.4.2 · Data structures, part 8 of 14.
WorksheetOCR H446 1.4.2 Graphs: concepts and representations
Part 7 · H446 1.4.2 · Data structures
Graph questions in H446 1.4.2 reward precise vocabulary, so this worksheet separates direction from weight and node from edge before any representation is chosen. A collaboration network of people, venues and routes gives students a graph to read accurately, then store as an adjacency list or an adjacency matrix. Students will: - distinguish directed from undirected and weighted from unweighted graphs - use node, edge, path, cycle and connectedness precisely rather than loosely - read the outgoing neighbours and weights of a node from a drawn graph - compare adjacency lists with adjacency matrices for a network with few connections per node - design a one-way weighted route system and justify direction, weight meaning and representation Inside: 7 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 21 marks, about 45 to 55 minutes. Series: H446 1.4.2 · Data structures, part 7 of 14.
WorksheetOCR H446 1.4.2 Linked lists: add and remove
Part 6 · H446 1.4.2 · Data structures
Changing a linked list means rewiring pointers in a safe order, and the wrong order silently orphans the rest of the data. This H446 1.4.2 worksheet takes students from insertion at the head and after a node through to removal of head, middle and final nodes, checking reachability after every change. Students will: - insert a node at the head and after a given node in an order that preserves the remainder - remove head, middle and final nodes without leaving data unreachable - state what actually changes on insertion, and what does not need to move - implement head removal and insertion after a node using nodes held as objects - compare an array-of-nodes implementation with an object-node one and name a shared invariant Inside: 8 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 2 written answers and 2 Python tasks. 23 marks, about 45 to 55 minutes. Series: H446 1.4.2 · Data structures, part 6 of 14.
WorksheetOCR H446 1.4.2 Linked lists: traversal and search
Part 5 · H446 1.4.2 · Data structures
Logical order in a linked list follows the links, not the row order of the array that stores the nodes, and that distinction is where students most often go wrong in H446 1.4.2. Using a playlist held as an array of nodes, this worksheet establishes the traversal invariant and applies it to searching. Students will: - identify head, data, next and the null value that ends a list - reconstruct the logical order of a list from an array of nodes - trace a search, separating a successful stop from reaching the end of the list - write a search that returns the index holding a target or reports its absence - compare following links with direct array indexing when retrieving a distant item Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers, 1 Python task and 1 trace table. 17 marks, about 40 to 50 minutes. Series: H446 1.4.2 · Data structures, part 5 of 14.
WorksheetOCR H446 1.4.2 Queues and circular arrays
Part 4 · H446 1.4.2 · Data structures
A support queue that serves the oldest waiting request first is the entry point to the first in, first out half of H446 1.4.2. This worksheet takes students through head, tail and count state in a circular array, where wraparound and the difference between empty and full are settled by the pointers rather than by what the array still holds. Students will: - enqueue and dequeue using head, tail and count together - model wraparound in a circular array and tell an empty queue from a full one - explain why shifting every remaining item after a dequeue is inefficient - implement an enqueue that rejects a full queue and updates state only on success - judge where strict first in, first out is unsuitable, such as emergency-priority requests Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 1 written answer, 1 Python task and 1 trace table. 19 marks, about 45 to 55 minutes. Series: H446 1.4.2 · Data structures, part 4 of 14.
WorksheetOCR H446 1.4.2 Stacks: behaviour and operations
Part 3 · H446 1.4.2 · Data structures
Stacks are examined in H446 1.4.2 as state, not just as a definition, so this worksheet fixes an explicit top-pointer convention and holds students to it. Push, pop and peek are traced on an array stack with a next-free-space pointer, so returned values, overflow and underflow are all decided by pointer state rather than by leftover array contents. Students will: - apply push, pop and peek under a stated next-free-space pointer convention - record the array contents, top pointer and returned value after each operation - detect overflow and underflow instead of reading a slot that is no longer part of the stack - implement a pop function that reports underflow rather than failing - explain why last in, first out suits nested calls and undo better than a first in, first out queue Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells, 1 written answer, 1 Python task and 1 trace table. 18 marks, about 45 to 55 minutes. Series: H446 1.4.2 · Data structures, part 3 of 14.
WorksheetOCR H446 1.4.2 Multidimensional structures in programs
Part 2 · H446 1.4.2 · Data structures
Dimensions are indexing decisions, not a measure of how realistic a model looks, and H446 1.4.2 asks students to keep every one of them meaningful. Working from a venue stored by floor, row and seat, this worksheet teaches confident indexing and ordered traversal of one, two and three-dimensional structures. Students will: - interpret an index into one, two and three-dimensional structures and say what each position selects - state the coordinates visited by a row-major traversal and the value stored at a given index - write nested loops that count matching elements in a 3D nested list of unstated size - explain when a list of records is clearer than a 2D array whose columns carry meaning - recall the naming of layers, rows and columns from memory in a closed-book check Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 2 Python tasks. 17 marks, about 40 to 50 minutes. Series: H446 1.4.2 · Data structures, part 2 of 14.
WorksheetOCR H446 1.4.2 Arrays, records, lists and tuples
Part 1 · H446 1.4.2 · Data structures
OCR H446 1.4.2 expects students to choose between arrays, records, lists and tuples rather than reach for whichever structure is most familiar. This worksheet builds that choice from shape, meaning, mutability and the operations a program actually performs, using a creative-events app that holds seat grids, performer details, editable set lists and fixed colour values. Students will: - describe arrays, records, lists and tuples in terms of shape, access and whether values may change - choose a structure for a described requirement and reject one close alternative with reasons - explain how traversal, update, addition and removal differ across the four structures - design storage for a changing ordered collection of player records with named fields - complete closed-book sentences on structure choice without an answer bank Inside: 8 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 21 marks, about 40 to 50 minutes. Series: H446 1.4.2 · Data structures, part 1 of 14.
WorksheetOCR H446 1.4.1 Data representation exam transition
Part 11 · H446 1.4.1 · Data types
An assessment piece for the end of H446 1.4.1, worked independently and without checking answers along the way. An original satellite-media scenario samples the whole specification point, from type choice and base conversion through signed arithmetic, floating-point addition, shifts, masks and character sets, so a teacher can see which method a student reaches for unprompted. Students will: - state suitable primitive data types for values in an unfamiliar scenario - complete mixed 8-bit binary, hexadecimal and denary conversions without prompts - represent and correct signed values in 8-bit two's complement, showing the method - align, calculate and normalise an OCR-format floating-point addition - review their own evidence and name the method to revisit before a timed assessment Inside: 1 explanation cell, 5 written answers and 5 number answers. 40 marks, about 55 to 70 minutes. Series: H446 1.4.1 · Data types, part 11 of 11.
WorksheetOCR H446 1.4.1 Data representation consolidation
Part 10 · H446 1.4.1 · Data types
No new content is introduced here: this is the consolidation piece that pulls the whole of H446 1.4.1 together. A live-event system mixing bookings, lighting values, signed sensor readings, audio, permission flags and messages means the questions never say which method to use, so students have to route to it themselves, starting from closed-book retrieval. Students will: - select the right representation method when the question does not name it - move between denary, 8-bit binary and hexadecimal in a mixed conversion table - interpret signed readings and complete fixed-width additions with the carry working shown - normalise and add values in the OCR floating-point format - read a shift or mask operation and state both the result and its purpose Inside: 4 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 2 written answers and 6 number answers. 42 marks, about 55 to 70 minutes. Series: H446 1.4.1 · Data types, part 10 of 11.
WorksheetOCR H446 1.4.1 Character sets
Part 9 · H446 1.4.1 · Data types
Turning characters into numbers and back is the H446 1.4.1 content here, and the worksheet keeps the character set and the encoding as separate ideas. A multilingual group chat supplies the context, and every code comes from a table given in the question, because the assessed skill is using a mapping rather than memorising code values. Students will: - explain why a sender and receiver need a compatible character mapping - convert a supplied character code between denary, hexadecimal and binary - decode a bit pattern and a hexadecimal code back into characters - describe what goes wrong when the same bits are read with an incompatible mapping - compare ASCII and Unicode, including a storage or transmission consequence of the encoding chosen Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 3 written answers and 2 number answers. 19 marks, about 35 to 45 minutes. Series: H446 1.4.1 · Data types, part 9 of 11.
WorksheetOCR H446 1.4.1 Bitwise shifts and masks
Part 8 · H446 1.4.1 · Data types
A status byte holding eight independent permission flags is the setting for the shift and mask content of H446 1.4.1. Shifts move every bit at a fixed width while masks select particular positions, and OCR credits the calculated result and the purpose of the operation separately, so students are asked for both each time. Students will: - apply logical left and right shifts at a fixed width, tracking discarded and inserted bits - state the multiplication or division effect of a shift and when that effect breaks down - choose between AND, OR and XOR to test, set, clear or toggle bits - design 8-bit masks for a stated purpose and explain why unselected bits are unchanged - complete a Python function that toggles the bits identified by a mask Inside: 8 explanation cells, 2 fill-in-the-blanks cells, 2 written answers, 1 Python task and 2 number answers. 32 marks, about 45 to 55 minutes. Series: H446 1.4.1 · Data types, part 8 of 11.
WorksheetOCR H446 1.4.1 Floating-point arithmetic
Part 7 · H446 1.4.1 · Data types
Once the fields can be read and normalised, H446 1.4.1 expects students to calculate with them and to show every stage. This is the arithmetic worksheet in the floating-point sequence, set in a digital mixer combining signed adjustments: exponents are aligned, signed mantissas are added or subtracted, results are normalised, and precision loss is diagnosed rather than ignored. Students will: - align two values to a common exponent before any mantissa arithmetic - add and subtract signed mantissas at a fixed width - normalise a result and adjust its exponent to match - explain why bits pushed out of the field during alignment cost precision - recognise when a correctly normalised result needs an exponent the field cannot hold Inside: 7 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 1 written answer and 2 number answers. 26 marks, about 50 to 60 minutes. Series: H446 1.4.1 · Data types, part 7 of 11.
WorksheetOCR H446 1.4.1 Floating-point normalisation
Part 6 · H446 1.4.1 · Data types
Several mantissa and exponent pairs can encode the same number, so H446 1.4.1 asks for the normalised form that makes full use of a finite mantissa. Students first learn to recognise a normalised value from its first two mantissa bits, for positive and negative values, then shift and compensate so the represented value is preserved. Students will: - decide whether a two's-complement mantissa is normalised, whether positive or negative - explain why the first two mantissa bits must differ - shift a mantissa and move the exponent in the opposite direction to preserve the value - normalise values using a 6-bit mantissa and a 4-bit exponent - diagnose what happens when a mantissa is shifted and the exponent is left unchanged Inside: 7 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 1 written answer and 2 number answers. 24 marks, about 45 to 55 minutes. Series: H446 1.4.1 · Data types, part 6 of 11.
WorksheetOCR H446 1.4.1 Binary floating-point representation
Part 5 · H446 1.4.1 · Data types
OCR's floating-point format for H446 1.4.1 uses a two's-complement mantissa and a two's-complement exponent, not IEEE 754, so students need the format the paper actually assesses. Working from audio and sensor values, this worksheet fixes where the binary point sits and then has students both interpret and construct values at a 6-bit mantissa and 4-bit exponent. Students will: - locate the mantissa and exponent fields and state where the binary point sits - interpret a stored value as a signed mantissa multiplied by a power of two - represent a denary value at a stated mantissa and exponent width - read a two's-complement exponent as signed rather than as an unsigned pattern - explain how mantissa width and exponent width affect precision and range differently Inside: 8 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell, 1 written answer and 2 number answers. 22 marks, about 45 to 55 minutes. Series: H446 1.4.1 · Data types, part 5 of 11.
WorksheetOCR H446 1.4.1 Binary integer arithmetic
Part 4 · H446 1.4.1 · Data types
Fixed-width addition and subtraction is where carries, borrows and overflow become examinable in H446 1.4.1, and the working carries marks as much as the answer does. A game server combining score changes gives the context for 8-bit addition, borrowing subtraction and two's-complement subtraction, before separating a carry out from signed overflow. Students will: - add pairs of 8-bit unsigned values and record the carry row - subtract 8-bit values by borrowing and by adding a two's complement - hold a result at the stated width and interpret the remaining bits - decide whether an addition has overflowed and give the representable-range reason - explain in writing why a carry out and signed overflow are not the same event Inside: 8 explanation cells, 1 fill-in-the-blanks cell, 1 written answer and 4 number answers. 37 marks, about 45 to 55 minutes. Series: H446 1.4.1 · Data types, part 4 of 11.
WorksheetOCR H446 1.4.1 Signed integers
Part 3 · H446 1.4.1 · Data types
Negative values have to fit the same fixed-width field as positive ones, and H446 1.4.1 covers both sign-and-magnitude and two's complement. Using a game that records temperature and score changes, the tasks keep all eight columns visible so the invert-and-add-one method and the signed place-value check are both shown. Students will: - represent and interpret 8-bit sign-and-magnitude values - convert a signed denary integer to 8-bit two's complement using invert and add one - check a two's-complement pattern with signed place values starting at minus 128 - compare the two representations on range and on how zero is stored - explain why a bit pattern cannot be interpreted until its encoding is named Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 1 written answer and 4 number answers. 28 marks, about 40 to 50 minutes. Series: H446 1.4.1 · Data types, part 3 of 11.
WorksheetOCR H446 1.4.1 Binary, hexadecimal and denary
Part 2 · H446 1.4.1 · Data types
A number base changes how a value is written, not the quantity stored, and H446 1.4.1 expects fluent conversion in both directions. Built around colour channels and device identifiers, this worksheet keeps place values and nibble grouping visible so students convert between 8-bit binary, two-digit hexadecimal and denary by method rather than by memory. Students will: - read an 8-bit pattern using the place values 128 down to 1 - convert positive denary values to 8-bit binary and back - group bits into nibbles to move between binary and two-digit hexadecimal - explain why hexadecimal is easier for a person to read without changing what is stored - complete the conversion definitions from memory in a closed-book check Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 1 written answer and 6 number answers. 24 marks, about 35 to 45 minutes. Series: H446 1.4.1 · Data types, part 2 of 11.
WorksheetOCR H446 1.4.1 Primitive data types and casting
Part 1 · H446 1.4.1 · Data types
OCR H446 1.4.1 asks students to choose a primitive data type from what a value represents and what the program does with it, not from how the value looks. Set in a music-event booking system, this worksheet builds that two-question method and then has students trace what casting really does to a value, including in running Python. Students will: - choose an OCR primitive type from a value's purpose and the operations needed - justify storing a fixed-format identifier as a string rather than an integer - trace the effect of a cast, including the loss of a fractional part - complete a Python function that casts supplied text, calculates a total and returns a set sentence - recall the type and casting definitions in a closed-book check Inside: 10 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells, 1 written answer and 2 Python tasks. 17 marks, about 40 to 50 minutes. Series: H446 1.4.1 · Data types, part 1 of 11.
WorksheetOCR H446 1.3.4 Web Technologies exam transition
Part 8 · H446 1.3.4 · Web technologies
The assessment closing the H446 1.3.4 sequence, meant to be worked independently and without checking answers along the way. It asks for HTML, CSS and JavaScript written to briefs, then for explanation of indexing and ranking and evaluation of where processing belongs. Students will: - write a page, an external stylesheet and a function to stated briefs under examination conditions - diagnose an identifier mismatch between a page and its script - explain how a page is discovered, indexed, updated and removed, and why results can lag - compare pages with different incoming-link profiles and state the limits of that reasoning - justify where each task in a service route runs, including why a server repeats a browser check Inside: 2 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 8 written answers. 64 marks, about 55 to 70 minutes. Series: H446 1.3.4 · Web technologies, part 8 of 8.
WorksheetOCR H446 1.3.4 Web Technologies consolidation
Part 7 · H446 1.3.4 · Web technologies
Consolidation for H446 1.3.4 built around a single community equipment page, so HTML, CSS, JavaScript, search-engine behaviour and processing location all have to hold together at once. No new required knowledge appears; the demand comes from using the ideas at the same time. Students will: - write matching HTML, external CSS and JavaScript for one described page - explain what breaks when an identifier's capitalisation differs between page and script - trace a new page from an incoming directory link to appearing in a query result - explain how a further incoming link could affect ranking without claiming a position - allocate the tasks in a booking route between browser and server and justify each Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 4 written answers. 37 marks, about 45 to 60 minutes. Series: H446 1.3.4 · Web technologies, part 7 of 8.
WorksheetOCR H446 1.3.4 Client-side and server-side processing
Part 6 · H446 1.3.4 · Web technologies
Deciding whether work happens in the browser or on the service's own infrastructure is the reasoning H446 1.3.4 rewards, and the language a task is written in is not the answer to it. This worksheet classifies tasks by data location, trust, responsiveness and shared state, then applies the split to a service running on weak devices over an unreliable connection. Students will: - classify tasks by where they run and say why that location is required - explain why a check made in the browser cannot be trusted on its own - identify the points where data crosses between browser and server - recommend a processing split for a service limited by device power and connection quality Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 27 marks, about 40 to 50 minutes. Series: H446 1.3.4 · Web technologies, part 6 of 8.
WorksheetOCR H446 1.3.4 PageRank link graphs
Part 5 · H446 1.3.4 · Web technologies
PageRank is required at H446 1.3.4 only as a high-level link-graph idea, with no numeric iteration and no code. This worksheet keeps students on the reasoning that is actually examined: the direction of a link, the importance of the page it comes from, and why counting links is not enough. Students will: - read arrow direction in a directed link graph before counting anything - compare pages whose incoming links differ in number and in source importance - explain why more incoming links is not a guaranteed advantage in the simplified model - separate index records and discovery from changes in the incoming-link graph - propose defensible actions for a poorly placed page without claiming an exact score or position Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 29 marks, about 40 to 50 minutes. Series: H446 1.3.4 · Web technologies, part 5 of 8.
WorksheetOCR H446 1.3.4 Search-engine indexing
Part 4 · H446 1.3.4 · Web technologies
Search results come from a provider's own index, not from a live sweep of the web at the moment someone submits a query. This worksheet holds crawling, indexing and query matching apart for H446 1.3.4, using a page that is discovered, changed and then removed to show why results can lag behind the live web. Students will: - describe how a crawler discovers pages by following links from pages it already knows - explain what a provider records in its index and what a query actually searches - account for the delay between a live page changing and search results changing - evaluate common claims about publishing, crawling and how results are retrieved Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 25 marks, about 35 to 45 minutes. Series: H446 1.3.4 · Web technologies, part 4 of 8.
WorksheetOCR H446 1.3.4 JavaScript and DOM interaction
Part 3 · H446 1.3.4 · Web technologies
JavaScript at H446 1.3.4 is about connecting familiar programming ideas to page elements, so exact syntax matters less than precise logic and precise element state. This worksheet traces a supplied function, exposes what an identifier mismatch does, then has students write interface behaviour of their own. Students will: - trace a function that reads an input, calculates and writes to a page element - record the variable values, displayed result and returned value at each step - explain what fails when a page element identifier and the script's lookup disagree - amend a function to add a condition while preserving its numeric result and return value - write a function that loops through an array of element identifiers and reports a count Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 35 marks, about 45 to 55 minutes. Series: H446 1.3.4 · Web technologies, part 3 of 8.
WorksheetOCR H446 1.3.4 CSS selectors and properties
Part 2 · H446 1.3.4 · Web technologies
CSS is examined in H446 1.3.4 as two halves, a selector that chooses elements and declarations that change presentation, and student errors almost always sit in one half or the other. This worksheet reads a rule apart into its parts, diagnoses a broken one, then asks for a stylesheet written to a brief. Students will: - match element, class and identifier selectors to the HTML they select - write declarations with correct property, value and punctuation - explain why an element given an identifier is not matched by a class selector - write external CSS to a stated brief covering colour, font, border and width - distinguish an inline style from an external stylesheet Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 27 marks, about 35 to 45 minutes. Series: H446 1.3.4 · Web technologies, part 2 of 8.
WorksheetOCR H446 1.3.4 HTML structure, content and forms
Part 1 · H446 1.3.4 · Web technologies
H446 1.3.4 expects students to read and write HTML using the language named in the specification's appendix, so this worksheet works from nested source to rendered page and back again. Students repair broken elements and attributes first, then write a complete page of their own. Students will: - read a nested HTML document and connect its elements to the regions a browser displays - repair misused attributes and missing container elements, explaining each repair - use named form controls for text, password and submit inputs - write a complete page with a heading, image, link, list and form, indented to show the nesting Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 29 marks, about 40 to 50 minutes. Series: H446 1.3.4 · Web technologies, part 1 of 8.
WorksheetOCR H446 1.3.3 Networks exam transition
Part 10 · H446 1.3.3 · Networks
This is the assessment closing the H446 1.3.3 sequence, written to be attempted independently and without checking answers along the way. It runs through protocols and standards, layering, DNS and packet transfer, switching, threats and controls, hardware and network models in examination-style questions. Students will: - explain protocols, standards and the reasons for layering under examination conditions - work through name resolution and packet transfer to a usable response - justify a switching choice for contrasting workloads and state the drawbacks accepted - diagnose four separate incidents and propose a defence for each - discuss a whole design for a multi-site organisation, covering scope, hardware, service model and security Inside: 2 explanation cells, 1 multiple-choice question and 9 written answers. 60 marks, about 55 to 70 minutes. Series: H446 1.3.3 · Networks, part 10 of 10.
WorksheetOCR H446 1.3.3 Networks consolidation
Part 9 · H446 1.3.3 · Networks
Consolidation across H446 1.3.3, introducing no new content but requiring transfer, switching, threats, controls, hardware and service models to be used together. Students trace one inter-site request end to end, then redesign the same network after an incident report. Students will: - explain an inter-site request from domain name to usable data across all four layers - recommend a switching approach for two contrasting workloads on the same site - identify what is missing from an incomplete explanation of why layering helps - diagnose several threats from one incident report and design a layered response with limitations - select hardware roles and a service model for the redesigned network and justify both Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 4 written answers. 45 marks, about 45 to 60 minutes. Series: H446 1.3.3 · Networks, part 9 of 10.
WorksheetOCR H446 1.3.3 Client server and peer to peer networks
Part 8 · H446 1.3.3 · Networks
Client-server and peer-to-peer are arrangements of responsibility rather than shapes on a diagram, and that is the distinction H446 1.3.3 rewards. This worksheet asks where services, access control, backup and maintenance are managed in each model, then follows the consequences for cost, scale and resilience. Students will: - describe where services, accounts and backups are managed in each model - explain what each arrangement means for cost, administration and resilience - recommend a model for a small, short-lived group and justify it from that context - compare the two models for a large organisation holding confidential shared records Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 24 marks, about 35 to 45 minutes. Series: H446 1.3.3 · Networks, part 8 of 10.
WorksheetOCR H446 1.3.3 Network hardware by purpose
Part 7 · H446 1.3.3 · Networks
H446 1.3.3 asks for the purpose of network hardware, not its internal electronics, and marks are lost when three devices all get described as things that connect devices. This worksheet makes every device description distinguishable from its neighbours, then asks students to build a sensible hardware route for an unfamiliar office. Students will: - describe the distinct purpose of a NIC, switch, router, wireless access point, modem, hub and cable - write device descriptions that could not be swapped between devices - follow traffic through the hardware it passes on the way to another network - select the minimum sensible hardware for a mixed wired and wireless site and justify each item Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 25 marks, about 40 to 50 minutes. Series: H446 1.3.3 · Networks, part 7 of 10.
WorksheetOCR H446 1.3.3 Network controls and layered protection
Part 6 · H446 1.3.3 · Networks
Having diagnosed threats in the previous worksheet, students here choose the protection. H446 1.3.3 expects a control to be justified by its mechanism against a plausible attack route, so every control proposed here also has to carry a limitation, which stops any single tool being presented as making a network secure. Students will: - explain the mechanism by which a control blocks a particular attack route - state a realistic limitation for each control they propose - combine complementary controls into a layered defence for a described site - explain why a firewall-only or encryption-only answer leaves gaps open Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 28 marks, about 40 to 50 minutes. Series: H446 1.3.3 · Networks, part 6 of 10.
WorksheetOCR H446 1.3.3 Network threats and attack paths
Part 5 · H446 1.3.3 · Networks
Naming a threat earns very little on its own. This is the diagnosis half of the H446 1.3.3 security material, connecting each threat to its attack route, its target and its consequence; the following worksheet turns to the controls that answer them. Students will: - describe the mechanism behind common network threats - work from incident evidence to a named threat rather than from the name backwards - distinguish threats that attack availability from those that attack confidentiality or integrity - diagnose several incidents reported together and keep the explanations distinct Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 26 marks, about 40 to 50 minutes. Series: H446 1.3.3 · Networks, part 5 of 10.
WorksheetOCR H446 1.3.3 Packet and circuit switching
Part 4 · H446 1.3.3 · Networks
Switching is easy to recite and harder to choose between, and that choice is where the H446 1.3.3 marks sit. This worksheet models packet and circuit switching side by side, then makes students recommend one for workloads whose constraints pull in different directions. Students will: - describe how each method allocates a route and capacity - compare the two methods on failure response, ordering and use of available capacity - justify a switching choice from the constraint a scenario actually states - state the drawback accepted by each recommendation rather than presenting one method as always better Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 24 marks, about 35 to 45 minutes. Series: H446 1.3.3 · Networks, part 4 of 10.
WorksheetOCR H446 1.3.3 Internet transfer, packets, IP addresses and DNS
Part 3 · H446 1.3.3 · Networks
A request that starts with a typed domain name and ends with a usable page passes through several distinct mechanisms, and H446 1.3.3 expects DNS, IP addressing and packet transfer to be kept apart. This worksheet walks the whole journey in order, then deliberately breaks it with packets that take different routes and arrive out of sequence. Students will: - describe how a domain name is resolved to an IP address - explain how data is divided into packets and what the control information supports - account for packets travelling by different routes and arriving out of order - trace one complete request and response from typed address to application data - explain why a receiver must reconstruct in the intended order rather than the order of arrival Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 23 marks, about 45 to 55 minutes. Series: H446 1.3.3 · Networks, part 3 of 10.
WorksheetOCR H446 1.3.3 TCP IP stack and protocol layering
Part 2 · H446 1.3.3 · Networks
The four-layer TCP/IP model is examined twice over in H446 1.3.3: what each layer is responsible for, and separately why dividing the job into layers is useful at all. This worksheet follows a message down the sending stack and back up the receiving one, then asks students to argue the benefits of layering in their own words. Students will: - state the responsibility of each of the four layers OCR requires - follow one message down a sending stack and up a receiving stack - explain benefits of layering by linking a feature of the model to the benefit that follows - place unfamiliar actions at the correct layer and give the direction of travel Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 23 marks, about 40 to 50 minutes. Series: H446 1.3.3 · Networks, part 2 of 10.
WorksheetOCR H446 1.3.3 Network purpose, protocols, standards, LANs and WANs
Part 1 · H446 1.3.3 · Networks
OCR H446 1.3.3 puts network purpose, protocols, standards and network scope within a few lines of each other, and students routinely blur them. This worksheet keeps the four ideas apart, then asks for benefits argued from an organisation's actual situation rather than from a memorised list. Students will: - separate a protocol from a standard, and both from the purpose of a network - describe LAN and WAN as questions of geographical scope and ownership of infrastructure - explain benefits of networking for a named single-site organisation without falling back on a LAN and WAN comparison - recommend a network scope for contrasting organisations and name a cost, management or security limitation for each Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 21 marks, about 35 to 45 minutes. Series: H446 1.3.3 · Networks, part 1 of 10.
WorksheetOCR H446 1.3.2 Databases exam transition
Part 13 · H446 1.3.2 · Databases
This is the assessment piece for H446 1.3.2: an original public-library scenario with much less support and no teaching between questions. It runs from key definitions and relationship justification through normalisation, SQL and integrity to transaction reasoning, and closes by asking students what to revisit. Students will: - explain and exemplify primary, foreign and secondary keys in an unfamiliar system - justify the relationships implied by a supplied set of tables - normalise a multi-table schema to third normal form without step-by-step support - write selection, nested and modification SQL for the library scenario - decide from evidence in their own attempt which database skill needs more work Inside: 2 explanation cells, 1 multiple-choice question and 11 written answers. 82 marks, about 80 minutes. Series: H446 1.3.2 · Databases, part 13 of 13.
WorksheetOCR H446 1.3.2 Databases consolidation
Part 12 · H446 1.3.2 · Databases
Every strand of H446 1.3.2 meets in one community-festival case here, from entity design and normalisation through SQL to indexing, integrity, transactions and data capture. No new specification content is introduced, so this works as a consolidation or revision session once the topic has been taught. Students will: - state the cardinalities in a supplied schema and explain how its keys support them - normalise the given design to third normal form and name the dependencies removed - write a multi-table query combining two conditions - write insertion and deletion statements for the same scenario - bring indexing, referential integrity, locking and capture methods to bear on a single case Inside: 4 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 7 written answers. 61 marks, about 70 to 85 minutes. Series: H446 1.3.2 · Databases, part 12 of 13.
WorksheetOCR H446 1.3.2 Transactions, ACID, locking and redundancy
Part 11 · H446 1.3.2 · Databases
A booking system meets its hardest test when two people want the last seat or the power fails mid-update. This worksheet covers the H446 1.3.2 reliability content: transactions, the four ACID properties, record locking, and the two very different meanings of redundancy. Students will: - explain a transaction as a unit of work that completes fully or not at all - apply each ACID property to a described failure or a clash between users - explain how record locking stops two users changing the same record, and give one drawback - separate harmful duplicated data from deliberate copies kept for recovery - design a reliable transaction approach for a scenario with simultaneous users and a replicated database Inside: 8 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 40 marks, about 35 to 50 minutes. Series: H446 1.3.2 · Databases, part 11 of 13.
WorksheetOCR H446 1.3.2 SQL INSERT, DELETE and DROP
Part 10 · H446 1.3.2 · Databases
INSERT, DELETE and DROP change a database at three very different scales, and confusing them is a common way to lose marks in H446 1.3.2. Students predict the resulting state of each statement, repair ones that are incomplete or unsafe, and consider what referential integrity does to a deletion. Students will: - distinguish adding a row, removing selected rows and removing a whole table - write an INSERT that names its fields explicitly rather than relying on field order - add a condition so that a deletion removes only the intended records - correct SQL statements with missing keywords or missing conditions - explain why deleting a referenced record may be rejected and give a safer approach Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells, 3 written answers and 1 Python task. 31 marks, about 25 to 40 minutes. Series: H446 1.3.2 · Databases, part 10 of 13.
WorksheetOCR H446 1.3.2 SQL joins and nested SELECT
Part 9 · H446 1.3.2 · Databases
Once data is split across tables, H446 1.3.2 expects queries that put it back together. This worksheet derives a join condition from the declared keys and evaluates a nested SELECT from the inner query outwards, which is the reading order students most often get wrong. Students will: - write a join condition matching a foreign key to the primary key it references - join three tables by starting from the one that holds the foreign keys - evaluate a nested SELECT inner query first and state the outer result - explain the evaluation order that produced a given set of rows - write both a join and a nested SELECT for an unfamiliar membership schema Inside: 8 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells, 3 written answers and 1 Python task. 32 marks, about 30 to 45 minutes. Series: H446 1.3.2 · Databases, part 9 of 13.
WorksheetOCR H446 1.3.2 SQL selection and conditions
Part 8 · H446 1.3.2 · Databases
SQL enters H446 1.3.2 here, held to the structures inside the OCR Appendix 5d assumed range. Students read a SELECT query clause by clause, predict exactly which rows it returns, then write their own using Boolean operators and wildcard patterns. Students will: - interpret SELECT, FROM and WHERE as separate parts of one query - predict the rows a supplied query returns from a given table and say why - combine two conditions with Boolean operators - use a wildcard pattern to match part of a text field - write queries for a new catalogue schema while staying inside the assumed SQL range Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells, 3 written answers and 1 Python task. 29 marks, about 25 to 40 minutes. Series: H446 1.3.2 · Databases, part 8 of 13.
WorksheetOCR H446 1.3.2 Indexing and referential integrity
Part 7 · H446 1.3.2 · Databases
Indexing and referential integrity are easily blurred together, so this H446 1.3.2 worksheet keeps them apart: one is about finding data quickly, the other about keeping the links between tables meaningful. Students trace lookups and parent-child operations, then weigh what an index costs to maintain. Students will: - explain how an index supports retrieval in a large table - decide whether an operation leaves every foreign key pointing at a record that exists - explain why a particular insertion, deletion or update would be rejected - weigh search speed against storage and update cost for a proposed index - design a safe procedure for deleting a record that other records still refer to Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 29 marks, about 25 to 40 minutes. Series: H446 1.3.2 · Databases, part 7 of 13.
WorksheetOCR H446 1.3.2 Capturing, selecting, managing and exchanging data
Part 6 · H446 1.3.2 · Databases
Beyond design, H446 1.3.2 asks how data gets into a database and how it is then selected, managed and exchanged. This worksheet follows that journey so students choose a capture or exchange method from the shape of the data and its destination, not from a memorised list. Students will: - distinguish capture, selection, management and exchange as separate stages - match a capture method to the form and volume of the source data - recommend a method for each stage of a described data journey - compare exchange formats for flat data and for data with nested lists - identify a risk or limitation at each stage and give a mitigation Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 35 marks, about 30 to 45 minutes. Series: H446 1.3.2 · Databases, part 6 of 13.
WorksheetOCR H446 1.3.2 Third normal form and complete normalisation
Part 5 · H446 1.3.2 · Databases
Third normal form removes dependencies between one non-key attribute and another, and H446 1.3.2 expects students to carry a relation the whole way from unnormalised data to 3NF. This worksheet keeps partial and transitive dependencies clearly apart and asks for the organisational benefit as well as the mechanics. Students will: - distinguish a partial dependency from a transitive one - follow a dependency chain to find the attribute that determines another - decompose a relation already in 2NF into third normal form with correct keys - distinguish update, insertion and deletion anomalies using the same data - normalise a multi-table clinic schema from first to third normal form Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 33 marks, about 30 to 45 minutes. Series: H446 1.3.2 · Databases, part 5 of 13.
WorksheetOCR H446 1.3.2 Second normal form
Part 4 · H446 1.3.2 · Databases
Second normal form only bites when a relation has a composite key, so partial dependency for H446 1.3.2 is taught here by testing each non-key attribute against both parts of that key. Students then decompose the relation and reconnect the resulting tables through their keys. Students will: - state the prerequisite and the dependency test for second normal form - trace which part of a composite key determines each non-key attribute - identify every partial dependency in a supplied relation - decompose a relation into tables that keep each fact reachable through keys - explain an update or insertion problem caused by leaving a partial dependency in place Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 28 marks, about 25 to 35 minutes. Series: H446 1.3.2 · Databases, part 4 of 13.
WorksheetOCR H446 1.3.2 First normal form
Part 3 · H446 1.3.2 · Databases
First normal form is the entry point to normalisation in H446 1.3.2, and this worksheet concentrates on spotting repeating groups and fields that hold several values at once. Students transform data into 1NF while checking that no fact has been lost on the way. Students will: - identify repeating groups and fields holding more than one value - rewrite unnormalised rows so that each field holds a single value - choose a key that stays unique after the transformation - check that the transformed design still preserves every original fact - explain why the absence of repeating groups does not prove a relation is in 2NF or 3NF Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 25 marks, about 25 to 35 minutes. Series: H446 1.3.2 · Databases, part 3 of 13.
WorksheetOCR H446 1.3.2 Entity relationships and linking tables
Part 2 · H446 1.3.2 · Databases
Cardinality is where students most often guess, so relationship modelling for H446 1.3.2 is taught here as a derivation from business rules and foreign-key placement. The worksheet also shows why a many-to-many relationship needs a linking table of its own. Students will: - read a relationship in both directions before naming its cardinality - distinguish one-to-one, one-to-many and many-to-many relationships - explain how a foreign key in a child table supports a stated relationship - correct a model that confuses the number of tables with the cardinality between them - specify an entity relationship model in words, including the linking table a many-to-many case requires Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 27 marks, about 25 to 35 minutes. Series: H446 1.3.2 · Databases, part 2 of 13.
WorksheetOCR H446 1.3.2 Database foundations, tables and keys
Part 1 · H446 1.3.2 · Databases
OCR H446 1.3.2 opens with the vocabulary everything else depends on: database, table, field, record, and the primary, foreign and secondary keys that link them. This worksheet builds that model from a ticket-booking scenario so students can justify a key choice rather than recite a definition. Students will: - distinguish a flat file design from a set of linked relational tables - identify primary, foreign and secondary keys from where a field appears in a schema - explain the job each key does in the table it sits in - propose tables and keys for an unfamiliar equipment-loan scenario - recall the core definitions from memory with no answer bank available Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 27 marks, about 25 to 35 minutes. Series: H446 1.3.2 · Databases, part 1 of 13.
WorksheetOCR H446 1.3.1 Compression, encryption and hashing exam transition
Part 7 · H446 1.3.1 · Compression, encryption and hashing
Sitting at the end of H446 1.3.1, this is an assessment to be completed independently and without checking answers along the way. It covers coding, encryption and hashing at examination weight and is written almost entirely as extended responses. Students will: - judge what is necessarily true of a lossless method - encode and decode run-length streams and reason about a sequence that would not benefit - construct and decode a dictionary-coded stream and explain why a decoder needs both parts - explain an asymmetric confidentiality route for a sender with no pre-shared secret, naming each key owner - decide between encryption and hashing for confidential messages, stored passwords and release-file checking Inside: 2 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 8 written answers. 50 marks, about 55 to 70 minutes. Series: H446 1.3.1 · Compression, encryption and hashing, part 7 of 7.
WorksheetOCR H446 1.3.1 Compression, encryption and hashing consolidation
Part 6 · H446 1.3.1 · Compression, encryption and hashing
Compression, encryption and hashing meet in one running project scenario here, which is the consolidation point for H446 1.3.1 rather than three separate topics revisited. No new content is introduced, so it works as a revision lesson or a checkpoint before the assessment. Students will: - recommend lossy or lossless compression for contrasting files within the same project - encode one sequence under both field orders and explain what a decoder must be told - build and decode a first-appearance dictionary, then account for its cost - trace an asymmetric confidentiality journey and say when a symmetric method becomes practical - trace password verification and a release-file digest check, stating what each match can support Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 5 written answers. 49 marks, about 45 to 60 minutes. Series: H446 1.3.1 · Compression, encryption and hashing, part 6 of 7.
WorksheetOCR H446 1.3.1 Hashing for password and data verification
Part 5 · H446 1.3.1 · Compression, encryption and hashing
Hashing and encryption are routinely confused in H446 1.3.1 answers. This worksheet holds the boundary firmly, treating a digest as something created, recreated and compared but never decrypted, and covers both password verification and checking a file after transfer. Students will: - describe hashing as a repeatable one-way mapping from input data to a digest - explain what a verification system should do with the password entered at login - set out account creation and a later login attempt as an ordered process - state what a digest comparison after a transfer does and does not evidence - distinguish encryption, secure password hashing and a hash table used to locate a record Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 32 marks, about 35 to 45 minutes. Series: H446 1.3.1 · Compression, encryption and hashing, part 5 of 7.
WorksheetOCR H446 1.3.1 Symmetric and asymmetric encryption
Part 4 · H446 1.3.1 · Compression, encryption and hashing
Key ownership is what encryption questions at H446 1.3.1 really test, and answers fail when the wrong person holds the wrong key. This worksheet traces symmetric and asymmetric journeys by owner and direction, then asks for choices justified from key distribution, speed and trust. Students will: - follow data through plaintext, ciphertext and decryption as separate states - name which key encrypts and which decrypts in an asymmetric confidentiality journey - explain why sending a shared secret key alongside the ciphertext is unsafe - recommend symmetric or asymmetric encryption from the constraints of a described situation - correct common claims about what encryption does and does not protect against Inside: 6 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 38 marks, about 45 to 55 minutes. Series: H446 1.3.1 · Compression, encryption and hashing, part 4 of 7.
WorksheetOCR H446 1.3.1 Dictionary coding
Part 3 · H446 1.3.1 · Compression, encryption and hashing
A dictionary-coded file is only complete when the dictionary travels with the coded stream, and H446 1.3.1 expects that cost to be counted before any saving is claimed. Dictionaries are built here by first appearance, decoded exactly, and compared against run-length encoding on the same data. Students will: - construct a dictionary and coded stream using first appearance to assign codes - state what a decoder needs in order to reconstruct the original exactly - decode a stream and check that spacing and punctuation survive the round trip - explain why dictionary coding can exploit repeats that are separated in the data - weigh the dictionary cost against the coded stream before claiming a reduction Inside: 6 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 28 marks, about 40 to 50 minutes. Series: H446 1.3.1 · Compression, encryption and hashing, part 3 of 7.
WorksheetOCR H446 1.3.1 Run-length encoding
Part 2 · H446 1.3.1 · Compression, encryption and hashing
Run-length encoding is examined at H446 1.3.1 as an exact, reversible process, and most lost marks come from the field order convention or from claiming a saving the data does not support. Students encode, decode and round-trip check streams under a stated convention, including the case where the representation grows. Students will: - segment a sequence into runs and store each run as a symbol and a count - explain why two separated runs of the same symbol cannot be merged into one pair - decode a supplied stream and check the reconstructed length - use run counts and stored overhead to say when run-length encoding helps and when it expands data - work to a count-then-symbol key and describe the error made by assuming the other order Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 26 marks, about 40 to 50 minutes. Series: H446 1.3.1 · Compression, encryption and hashing, part 2 of 7.
WorksheetOCR H446 1.3.1 Compression need, lossy and lossless choice
Part 1 · H446 1.3.1 · Compression, encryption and hashing
H446 1.3.1 asks not which method makes the smaller file but what a use case needs once the data is reconstructed. This worksheet builds that reconstruction test and applies it to lossy and lossless choices across contexts where the right answer changes. Students will: - explain why storage, bandwidth and transfer time make compression worthwhile - describe what happens to data across its original, compressed and reconstructed states - identify a use that clearly requires exact reconstruction - compare lossy and lossless compression using the same criterion on both sides - recommend a method for a medical scan, speech over a slow link and a configuration file, with reasons Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 29 marks, about 35 to 45 minutes. Series: H446 1.3.1 · Compression, encryption and hashing, part 1 of 7.
WorksheetOCR H446 1.2.4 Programming Languages exam transition
Part 10 · H446 1.2.4 · Types of programming language
An assessment for H446 1.2.4, intended to be worked independently and without checking answers along the way. It covers the whole topic at examination weight: paired language comparisons, LMC tracing, listing completion and construction, addressing resolution and object-oriented design. Students will: - give paired differences between assembly and high-level languages under examination conditions - discuss and justify more than one language choice within a single system - trace an LMC routine and complete an input loop that halts when a zero is supplied - write LMC code that outputs the smaller of two inputs exactly once - design a class with validated state and subclasses that override a shared summary method Inside: 3 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 7 written answers and 1 trace table. 56 marks, about 65 to 80 minutes. Series: H446 1.2.4 · Types of programming language, part 10 of 10.
WorksheetOCR H446 1.2.4 Programming Languages consolidation
Part 9 · H446 1.2.4 · Types of programming language
The consolidation piece for H446 1.2.4, bringing language choice, LMC execution, addressing modes and object-oriented design together in two running scenarios rather than revisiting each topic separately. No new content is introduced, so it suits a revision lesson or a checkpoint before assessment. Students will: - recommend and compare language levels for a portable application and a memory-constrained controller - trace one LMC execution that accepts several inputs and produces cumulative outputs - explain the output fault caused by removing a store instruction - resolve all four addressing modes against a single supplied memory state - write a class hierarchy that combines a validated capacity change with an overridden display method Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 5 written answers and 1 trace table. 44 marks, about 55 to 70 minutes. Series: H446 1.2.4 · Types of programming language, part 9 of 10.
WorksheetOCR H446 1.2.4 Inheritance, overriding and polymorphism
Part 8 · H446 1.2.4 · Types of programming language
Inheritance, overriding and polymorphism are examined together at H446 1.2.4 because they only make sense as one mechanism: a shared method name whose behaviour follows the actual type of the object. This worksheet traces that through an alert hierarchy, then asks students to design and explain their own. Students will: - describe how a subclass reuses and specialises a superclass definition - identify what makes a loop calling one shared method name polymorphic - state which overridden implementation runs for each object in a mixed collection - write an OCR-style hierarchy with a superclass and two subclasses that override the same method - explain why unrelated method names give specialised behaviour without a common polymorphic interface Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 27 marks, about 40 to 50 minutes. Series: H446 1.2.4 · Types of programming language, part 8 of 10.
WorksheetOCR H446 1.2.4 Encapsulation and controlled object state
Part 7 · H446 1.2.4 · Types of programming language
Encapsulation is often reduced to making things private, which does not earn the marks at H446 1.2.4. Students connect visibility to the rule an object must keep true, repair an unsafe public interface and then design controlled access for a class of their own. Students will: - explain encapsulation as controlled access that protects a rule about object state - describe what an unprotected public attribute allows any caller to do - redesign a class whose public attributes permit an invalid combination of values - specify which values a state-changing method should reject - compare a controlled method interface with directly writable public data Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 20 marks, about 35 to 45 minutes. Series: H446 1.2.4 · Types of programming language, part 7 of 10.
WorksheetOCR H446 1.2.4 OOP classes, objects, attributes, methods and constructors
Part 6 · H446 1.2.4 · Types of programming language
Object-oriented questions at H446 1.2.4 start with precise vocabulary: a class defines, an object holds its own state, and a constructor initialises a new instance from the parameters it was given. This worksheet separates those ideas and has students write coherent OCR-style class definitions. Students will: - distinguish a class definition from an object and its individual state - recognise a constructor that follows its stated parameters rather than asking for fresh input - explain why updating one object leaves another instance of the same class unchanged - state the resulting attribute values of two separate objects after a method call - write an OCR-style class with private attributes, a constructor and public methods Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 23 marks, about 40 to 50 minutes. Series: H446 1.2.4 · Types of programming language, part 6 of 10.
WorksheetOCR H446 1.2.4 Immediate, direct, indirect and indexed addressing
Part 5 · H446 1.2.4 · Types of programming language
Addressing modes cost marks at H446 1.2.4 when students name a mode without following where its operand actually leads. Immediate, direct, indirect and indexed addressing are resolved here against one fixed memory state, and then chosen and justified for a described task. Students will: - describe the route from an instruction's operand to the value it finally uses - state the effective address, where one exists, for each of the four modes - resolve all four modes against a supplied memory map and index value - design a memory map in which direct and indirect addressing return different values - explain why indexed addressing suits a loop over a contiguous array Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 27 marks, about 40 to 50 minutes. Series: H446 1.2.4 · Types of programming language, part 5 of 10.
WorksheetOCR H446 1.2.4 LMC control flow: trace, amend and write
Part 4 · H446 1.2.4 · Types of programming language
Branch instructions turn a straight LMC listing into a decision or a loop, and H446 1.2.4 expects a program that behaves correctly on every permitted path. Following on from basic LMC tracing, this worksheet covers BRA, BRZ and BRP, repeated input within one execution, and the faults that appear when a halt or a comparison boundary is wrong. Students will: - decide which branch is taken from the accumulator value immediately before it - trace a two-path program and record the single output produced before HLT - trace one execution supplied with several inputs, recording each return to the start label and the final halt - diagnose the fault caused by a missing HLT and state the repair - amend and then write LMC routines that classify a boundary value correctly and halt on every path Inside: 6 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell, 3 written answers and 2 trace tables. 21 marks, about 55 to 65 minutes. Series: H446 1.2.4 · Types of programming language, part 4 of 10.
WorksheetOCR H446 1.2.4 LMC machine, mnemonics and tracing
Part 3 · H446 1.2.4 · Types of programming language
The Little Man Computer is the model H446 1.2.4 uses to make low-level execution visible. Students build that state model, trace a complete routine instruction by instruction and complete a working mnemonic listing, so the accumulator, mailboxes and output are read as changing state rather than memorised from a table. Students will: - describe the input, accumulator, mailbox, instruction and output parts of the LMC model - trace a short routine through to HLT, recording the accumulator, changed mailboxes and each output - distinguish a DAT data location from an executable instruction - complete the missing mnemonics and operands so a sensor routine works end to end - explain the state changes caused by a load, add and store sequence on named mailboxes Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 1 written answer and 1 trace table. 14 marks, about 40 to 50 minutes. Series: H446 1.2.4 · Types of programming language, part 3 of 10.
WorksheetOCR H446 1.2.4 Procedural languages: read, trace, amend and write
Part 2 · H446 1.2.4 · Types of programming language
Procedural programming is examined through working code, so H446 1.2.4 rewards students who can follow state rather than recite a list of features. This worksheet works one small parameterised routine hard, tracing it, amending it against a new requirement and then writing a fresh procedure from a specification. Students will: - trace variables, a loop condition, a running total and the returned value through a parameterised call - explain why a total is initialised before the loop that adds to it - choose between count-controlled and condition-controlled iteration from what governs the repetition - amend a routine's comparison and selection logic, then predict the strings it returns - write and test a procedure that counts exact matches in a list, including an empty or no-match case Inside: 6 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell, 2 written answers and 1 trace table. 21 marks, about 40 to 50 minutes. Series: H446 1.2.4 · Types of programming language, part 2 of 10.
WorksheetOCR H446 1.2.4 Paradigms, language levels and contextual choice
Part 1 · H446 1.2.4 · Types of programming language
OCR H446 1.2.4 treats language level and programming paradigm as two separate classifications, but examination answers often collapse them into a vague claim that high-level languages are easier. This worksheet keeps the two questions apart and builds matched comparisons that tie a mechanism to its consequence. Students will: - separate the question of language level from the question of paradigm - judge whether a statement about language level is accurate - compare assembly and high-level code using the same criteria on both sides - recommend a language level and organisational approach for a portable app, memory-limited firmware and a large team-maintained simulation - justify each recommendation from the stated project constraints Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 21 marks, about 30 to 40 minutes. Series: H446 1.2.4 · Types of programming language, part 1 of 10.
WorksheetOCR H446 1.2.3 Software Development exam transition
Part 6 · H446 1.2.3 · Software development
This assessment closes H446 1.2.3, worked independently and without checking answers along the way. Methodology questions in examination phrasing come first, then tracing, fault diagnosis and full algorithm construction, including the file effects candidates most often leave out. Students will: - answer methodology questions to the command word and the evidence given - justify waterfall, spiral, agile with XP, or RAD for contrasting project briefs - discuss competing approaches for one project and commit to a recommendation - trace a supplied algorithm and explain why a counted result differs from the number of inputs - write code that calls a supplied function, stores every returned value and writes to a file Inside: 2 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells, 9 written answers and 1 trace table. 66 marks, about 60 to 75 minutes. Series: H446 1.2.3 · Software development, part 6 of 6.
WorksheetOCR H446 1.2.3 Software Development mastery and transfer
Part 5 · H446 1.2.3 · Software development
One ticketing project carries both halves of H446 1.2.3 here: methodology reasoning in the first episode, then algorithm tracing and construction in the second. Nothing new is taught, so it works as consolidation once both strands have been covered separately. Students will: - give paired differences between waterfall and spiral for a single described project - organise a project using one methodology or a clearly explained combination - explain how changed constraints alter the earlier methodology reasoning - trace a supplied algorithm and account for how the final total is formed - write code that uses a supplied function, stores its results and appends a total to a file Inside: 5 explanation cells, 2 fill-in-the-blanks cells, 6 written answers and 1 trace table. 49 marks, about 50 to 65 minutes. Series: H446 1.2.3 · Software development, part 5 of 6.
WorksheetOCR H446 1.2.3 Writing, following and using algorithms
Part 4 · H446 1.2.3 · Software development
The algorithm strand of H446 1.2.3 rewards preserved logic rather than perfect syntax, since coherent pseudocode or program code is accepted. Students here follow state through a trace, use a supplied helper function instead of rewriting it, repair a broken call, and then construct algorithms that include every required input, returned value and file effect. Students will: - trace an algorithm and record how each variable changes on every iteration - explain the relationship between a returned value and the variable that stores it - call a supplied function correctly rather than duplicating its rules - complete runnable Python that uses a helper and returns the required list - write an algorithm that covers ordered file effects such as appending and closing Inside: 8 explanation cells, 1 multiple-choice question, 3 fill-in-the-blanks cells, 4 written answers, 1 Python task and 1 trace table. 39 marks, about 50 to 65 minutes. Series: H446 1.2.3 · Software development, part 4 of 6.
WorksheetOCR H446 1.2.3 Comparing and selecting methodologies
Part 3 · H446 1.2.3 · Software development
There is no universal best methodology in H446 1.2.3, only a choice defended from the evidence a context supplies. This worksheet drills the selection routine, reading the constraints, naming a process mechanism, stating its consequence and admitting a cost, then revising the choice when new facts arrive. Students will: - extract the constraints that matter from a described project brief - connect a process mechanism to a constraint and then to a project consequence - recommend a methodology and explain why a named alternative fits less well - revise a recommendation when new evidence removes a risk or fixes a requirement - explain why blanket slogans about cost, planning or code quality are unsafe Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 40 marks, about 45 to 60 minutes. Series: H446 1.2.3 · Software development, part 3 of 6.
WorksheetOCR H446 1.2.3 Agile methodologies, XP and RAD
Part 2 · H446 1.2.3 · Software development
Agile development, extreme programming and rapid application development all respond to change, and H446 1.2.3 credit comes from explaining how each one does it and what it demands of people, feedback and technical capacity. This worksheet keeps the boundaries between the three visible while students apply them to briefs whose requirements are still moving. Students will: - place extreme programming and RAD correctly in relation to agile development - explain how named XP practices support a frequently changing codebase, with a limiting condition - distinguish an agile increment from a RAD prototype in the same context - judge suitability when users are unavailable or safety requirements are fixed - correct shorthand advice such as RAD meaning simply coding faster Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 34 marks, about 45 to 55 minutes. Series: H446 1.2.3 · Software development, part 2 of 6.
WorksheetOCR H446 1.2.3 Waterfall lifecycle and spiral model
Part 1 · H446 1.2.3 · Software development
H446 1.2.3 asks not what waterfall and spiral are called but what their movement changes for a project. This worksheet traces a linear route and a risk-driven cycle against contrasting briefs, so iteration, risk and change are argued as consequences rather than as labels. Students will: - follow the stages of a waterfall lifecycle and the repeating structure of a spiral cycle - explain a benefit and a drawback of waterfall for a project with fixed, signed-off rules - design a first spiral cycle with an objective, a major risk and a risk-reduction activity - explain how evidence from one cycle changes the plan for the next - compare both routes for a project carrying safety and integration risk, then recommend one Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 36 marks, about 45 to 55 minutes. Series: H446 1.2.3 · Software development, part 1 of 6.
WorksheetOCR H446 1.2.2 Applications Generation exam transition
Part 7 · H446 1.2.2 · Applications generation
This is the assessment piece for H446 1.2.2, worked independently and without checking answers along the way. It covers the topic in examination phrasing, from naming application types for a described brief to an integrated recommendation for a complete software generation route. Students will: - answer to the command word and the constraints a context actually supplies - justify application and utility choices from the functions a described organisation needs - explain matched translator differences and the stages a statement passes through - evaluate the benefits and drawbacks of depending on an external library over a long life - integrate translator, library, linker and loader reasoning into one recommendation Inside: 2 explanation cells, 1 multiple-choice question, 3 fill-in-the-blanks cells and 8 written answers. 83 marks, about 65 to 80 minutes. Series: H446 1.2.2 · Applications generation, part 7 of 7.
WorksheetOCR H446 1.2.2 Applications Generation mastery and transfer
Part 6 · H446 1.2.2 · Applications generation
Two extended development contexts pull the whole of H446 1.2.2 together here, covering software types, source models, translators, compilation stages and the library, linker and loader chain. No new content is introduced, so this belongs after the topic has been taught, at the point where students know the parts separately and need to combine them. Students will: - retrieve the topic's distinctions from memory before applying them in context - choose software and utilities for a mixed organisational brief and justify each from function - reach a conditional recommendation between a self-hosted open route and a managed closed one - trace one statement from tokens through to code placed in memory and running - weigh library benefits against drawbacks and repair a claim about reusing tested code Inside: 5 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 5 written answers. 71 marks, about 50 to 65 minutes. Series: H446 1.2.2 · Applications generation, part 6 of 7.
WorksheetOCR H446 1.2.2 Libraries, linkers and loaders
Part 5 · H446 1.2.2 · Applications generation
A library, a linker and a loader are distinguished in H446 1.2.2 by reusable code, combination at build time and placement in memory at run time. This worksheet follows compiled modules all the way to a running program, so that a build failure and a launch failure are diagnosed to the right tool. Students will: - describe what a library provides and what a linker combines into a single executable - explain the loader's run-time role in placing code and data into main memory - develop several distinct benefits of using an external library beyond a one-word claim - state risks of depending on external library code and pair a mitigation with each - distinguish an unresolved-routine build failure from a failure to load at launch Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 5 written answers. 51 marks, about 40 to 50 minutes. Series: H446 1.2.2 · Applications generation, part 5 of 7.
WorksheetOCR H446 1.2.2 Stages of compilation
Part 4 · H446 1.2.2 · Applications generation
Lexical analysis, syntax analysis, code generation and optimisation are examined in H446 1.2.2 through the evidence each stage receives and hands on. Working a single assignment statement through the whole sequence, this worksheet ties every stage to something visible, such as a token stream or an abstract syntax tree. Students will: - describe what lexical analysis removes, preserves and produces from source code - explain what syntax analysis checks and the structure it builds from the tokens - trace one statement through tokens, tree structure and generated code - identify which stage reports a given error and what then reaches the next stage - state the purpose of optimisation and the limits of what it may change Inside: 6 explanation cells, 1 multiple-choice question, 3 fill-in-the-blanks cells and 4 written answers. 40 marks, about 45 to 55 minutes. Series: H446 1.2.2 · Applications generation, part 4 of 7.
WorksheetOCR H446 1.2.2 Interpreters, compilers and assemblers
Part 3 · H446 1.2.2 · Applications generation
Assemblers, compilers and interpreters are separated in H446 1.2.2 by their input, the moment translation happens, what they produce and whether that output can be reused. This worksheet traces all three routes alongside each other so that students offer a benefit with a consequence rather than a restated feature. Students will: - trace assembly source and high-level source along their different translation routes - state compiler and interpreter differences by comparing the same criterion on both sides - explain a development benefit of interpreting and a distribution benefit of compiling - choose a translation route from stated project constraints and justify it - recognise where the simplified examined model differs from real translator behaviour Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 5 written answers. 38 marks, about 45 to 55 minutes. Series: H446 1.2.2 · Applications generation, part 3 of 7.
WorksheetOCR H446 1.2.2 Open and closed source
Part 2 · H446 1.2.2 · Applications generation
Open- and closed-source questions in H446 1.2.2 turn on source access, licence permissions and who carries the consequences. This worksheet keeps the creator and the user in view at the same time, so students argue from control and licence terms rather than from price. Students will: - separate access to source code from what a licence actually permits - attach every stated benefit or drawback to a named stakeholder - compare a self-hosted open route with a managed closed service under long-term constraints - qualify claims such as 'open means free' or 'closed means supported' with the missing condition - recommend a source model for two contrasting organisations and name a risk each carries Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 5 written answers. 42 marks, about 40 to 50 minutes. Series: H446 1.2.2 · Applications generation, part 2 of 7.
WorksheetOCR H446 1.2.2 Applications and utilities
Part 1 · H446 1.2.2 · Applications generation
OCR H446 1.2.2 expects students to tell application, system and utility software apart by what each one is for, not by how familiar it looks. This worksheet builds a purpose-first selection chain, running from a task to the functions it requires and then to a software type, so students can justify a choice in a context they have never met. Students will: - classify a piece of software as application, system or utility from its purpose - work from a described task to its required functions and then to a software type - select application types for a mixed brief and defend each against those functions - state the precise purpose of a utility and the consequence it delivers on a given device - correct loose claims such as treating any useful program as a utility Inside: 5 explanation cells, 1 multiple-choice question, 3 fill-in-the-blanks cells and 4 written answers. 39 marks, about 35 to 45 minutes. Series: H446 1.2.2 · Applications generation, part 1 of 7.
WorksheetOCR H446 1.2.1 Systems software exam transition
Part 12 · H446 1.2.1 · Systems software
The assessment that closes H446 1.2.1. Nine original exam-style questions, worked independently, run across operating-system functions, paging and segmentation, virtual memory, interrupts, scheduling, classifications, BIOS and drivers, and virtual machines, finishing with a diagnose-and-repair question. Students will: - explain operating-system functions with reference to a supplied shared-computer context - explain how virtual memory can make a heavily loaded laptop very slow - describe how the processor handles a higher-priority interrupt and returns to its program - match named scheduling algorithms to a print service and to an interactive system - identify and correct misconceptions that cut across several parts of the specification Inside: 11 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 7 written answers. 47 marks, about 55 to 70 minutes. Series: H446 1.2.1 · Systems software, part 12 of 12.
WorksheetOCR H446 1.2.1 Systems software consolidation
Part 11 · H446 1.2.1 · Systems software
A consolidation worksheet that interleaves the whole of H446 1.2.1 instead of revisiting topics one at a time, so memory management, interrupts, scheduling, classifications and virtualisation all appear inside the same systems. It is built to reveal the one mechanism or distinction that needs repair before exam practice begins. Students will: - separate scattered free memory from insufficient RAM when both appear in one system - order the stages that follow acceptance of a higher-priority interrupt - compare round robin with a multi-level feedback queue and recommend one for a mixed workload - place the BIOS, a device driver and an operating-system virtual machine at the correct stage - assess the risk of relying on virtual machines and virtual memory together on one host Inside: 5 explanation cells, 4 multiple-choice questions, 3 fill-in-the-blanks cells and 4 written answers. 43 marks, about 45 to 60 minutes. Series: H446 1.2.1 · Systems software, part 11 of 12.
WorksheetOCR H446 1.2.1 Virtual machines
Part 10 · H446 1.2.1 · Systems software
OCR uses virtual machine broadly, so H446 1.2.1 covers two quite different things under one name: software presenting a computer so a guest operating system can run inside a host, and software that executes intermediate code. This worksheet keeps them apart and evaluates virtualisation on isolation, resources and portability. Students will: - distinguish a virtual machine hosting a guest operating system from one running intermediate code - explain how several virtual servers can run on one physical server - explain why the same intermediate code can be distributed to different processor types - weigh benefits and drawbacks of running guest operating systems in virtual machines - choose the right virtual concept by asking which function is being replaced Inside: 6 explanation cells, 4 multiple-choice questions, 3 fill-in-the-blanks cells and 5 written answers. 41 marks, about 45 to 60 minutes. Series: H446 1.2.1 · Systems software, part 10 of 12.
WorksheetOCR H446 1.2.1 BIOS and device drivers
Part 9 · H446 1.2.1 · Systems software
BIOS and device drivers are both systems software acting at different moments, which is exactly where H446 1.2.1 answers slip. This worksheet places the BIOS inside the start-up sequence and the driver inside the running system, translating generic operating-system requests into commands a particular device understands. Students will: - describe the steps from pressing the power button to the operating system taking control - state what the power-on self-test does and when control passes on - explain why a hardware device needs a driver - explain how one word processor can print correctly to two very different printer models - compare the role of the BIOS with the role of a device driver Inside: 4 explanation cells, 6 multiple-choice questions, 3 fill-in-the-blanks cells and 3 written answers. 31 marks, about 35 to 45 minutes. Series: H446 1.2.1 · Systems software, part 9 of 12.
WorksheetOCR H446 1.2.1 Types of operating system
Part 8 · H446 1.2.1 · Systems software
H446 1.2.1 names five operating-system classifications, and real installations often carry more than one at a time. This worksheet defines distributed, embedded, multi-tasking, multi-user and real time by the service each provides, then asks students to defend overlapping labels for unfamiliar systems. Students will: - define each of the five classifications by its defining behaviour rather than by example - explain what separates multi-user from multi-tasking - explain why a system that is fast on average can still fail a real-time requirement - justify more than one classification applying to a single installation - compare an embedded operating system with a general desktop operating system Inside: 4 explanation cells, 4 multiple-choice questions, 3 fill-in-the-blanks cells and 4 written answers. 34 marks, about 40 to 50 minutes. Series: H446 1.2.1 · Systems software, part 8 of 12.
WorksheetOCR H446 1.2.1 MLFQ and scheduler selection
Part 7 · H446 1.2.1 · Systems software
Multi-level feedback queues complete the five scheduling algorithms named in H446 1.2.1, and this worksheet uses them to pull the whole set together: several ready queues with different quantums, and processes moving between them according to observed behaviour. The second half is pure selection under stated constraints. Students will: - describe how processes move between the queues of a multi-level feedback queue - explain why a process that repeatedly uses its whole quantum may be moved down - set out the decision rule and pre-emption behaviour of all five named algorithms - recommend and justify an algorithm for print, interactive and short-request workloads - assess the intended benefit and the possible cost of short high-priority quantums Inside: 5 explanation cells, 4 multiple-choice questions, 3 fill-in-the-blanks cells and 4 written answers. 38 marks, about 45 to 55 minutes. Series: H446 1.2.1 · Systems software, part 7 of 12.
WorksheetOCR H446 1.2.1 Shortest job and shortest remaining time
Part 6 · H446 1.2.1 · Systems software
Shortest job first and shortest remaining time sound alike and schedule differently, and the single difference between them, pre-emption, changes the whole timeline. This H446 1.2.1 worksheet works through arrivals and remaining times so students can say which algorithm a given schedule actually demonstrates. Students will: - state the decision rule for shortest job first and for shortest remaining time - explain why both rely on estimated execution times and what inaccurate estimates cost - trace a schedule in which a later arrival changes which process runs - recommend one of the two for a service receiving unpredictable short requests - diagnose a mislabelled schedule and name the algorithm it really shows Inside: 5 explanation cells, 4 multiple-choice questions, 3 fill-in-the-blanks cells and 4 written answers. 32 marks, about 40 to 50 minutes. Series: H446 1.2.1 · Systems software, part 6 of 12.
WorksheetOCR H446 1.2.1 Scheduling with FCFS and round robin
Part 5 · H446 1.2.1 · Systems software
Scheduling begins here for H446 1.2.1. The worksheet introduces the ready, running and blocked process states, then has students build schedules by hand: first come first served in arrival order, and round robin rotating unfinished processes to the back of the queue after a fixed quantum. Students will: - describe the ready, running and blocked states and what moves a process between them - apply first come first served rules to a queue of arriving jobs - construct a round-robin trace for a given time quantum - explain the likely effect of making the quantum extremely small - compare the two algorithms for one long job followed by several short interactive jobs Inside: 6 explanation cells, 4 multiple-choice questions, 4 fill-in-the-blanks cells and 3 written answers. 37 marks, about 45 to 55 minutes. Series: H446 1.2.1 · Systems software, part 5 of 12.
WorksheetOCR H446 1.2.1 Interrupts, ISR and the FDE cycle
Part 4 · H446 1.2.1 · Systems software
Interrupt answers in H446 1.2.1 usually go wrong on ordering, so this worksheet rebuilds the sequence around the fetch, decode and execute cycle: the check happens at an instruction boundary, register state is saved to the stack, the service routine runs, then the interrupted program resumes exactly where it stopped. Students will: - distinguish the interrupt signal from the interrupt service routine that deals with it - place the priority check at the correct point in the instruction cycle - explain why register values are saved before the service routine runs - explain how the stack makes nested interrupt handling possible - correct the claim that an interrupt is handled part-way through an instruction Inside: 4 explanation cells, 5 multiple-choice questions, 3 fill-in-the-blanks cells and 3 written answers. 32 marks, about 40 to 50 minutes. Series: H446 1.2.1 · Systems software, part 4 of 12.
WorksheetOCR H446 1.2.1 Virtual memory
Part 3 · H446 1.2.1 · Systems software
Virtual memory looks like extra RAM and behaves nothing like it, which is the misconception H446 1.2.1 keeps testing. This worksheet traces the managed movement of pages between RAM and secondary storage, then follows the chain from a missing page to much slower access and, once it repeats, thrashing. Students will: - describe how the operating system moves pages between RAM and secondary storage - explain why describing virtual memory as extra RAM is misleading - link repeated swapping to slower access and to thrashing - state one benefit and one drawback of using virtual memory - tell virtual memory, virtual storage and virtual machines apart in context Inside: 6 explanation cells, 6 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 28 marks, about 35 to 45 minutes. Series: H446 1.2.1 · Systems software, part 3 of 12.
WorksheetOCR H446 1.2.1 Paging and segmentation
Part 2 · H446 1.2.1 · Systems software
Paging and segmentation both divide memory, and H446 1.2.1 answers lose marks by blurring them. This worksheet fixes the distinction on four points: how the division is made, where the parts are placed in RAM, how they are mapped back to the program, and which kind of fragmentation follows. Students will: - distinguish equal fixed-size pages from variable-size logical segments - read a page table to explain why storage order need not match program order - separate internal from external fragmentation and state the cause of each - recommend paging or segmentation for a described program and acknowledge one limitation - explain how controlled memory allocation protects one process from another Inside: 6 explanation cells, 5 multiple-choice questions, 3 fill-in-the-blanks cells and 3 written answers. 28 marks, about 40 to 50 minutes. Series: H446 1.2.1 · Systems software, part 2 of 12.
WorksheetOCR H446 1.2.1 Operating system purpose and functions
Part 1 · H446 1.2.1 · Systems software
The opening worksheet for H446 1.2.1 sets out what an operating system is for: hardware with very different jobs, many programs wanting it at once, and one managed layer coordinating the requests. It moves students from naming a function to explaining the mechanism behind it and the consequence for the user. Students will: - explain why a general-purpose computer needs an operating system at all - identify which operating-system function a described user action engages - describe memory, file, process, user and peripheral management with the purpose of each - explain how resource management keeps several open applications responsive - give two reasons applications reach hardware through the operating system rather than directly Inside: 5 explanation cells, 5 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 30 marks, about 35 to 45 minutes. Series: H446 1.2.1 · Systems software, part 1 of 12.
WorksheetOCR H446 1.1.3 Input, output and storage exam transition
Part 6 · H446 1.1.3 · Input, output and storage
An assessment piece that closes H446 1.1.3. Students work closed-book through original exam-style questions on device justification, storage recommendation, RAM and ROM behaviour and virtual storage, so a teacher can see which reasoning holds up without the worked examples in front of them. Students will: - distinguish a storage type from a storage device under assessment conditions - justify an input and an output device by their exact use in a described system - recommend storage for a constrained portable system and name a rejected alternative - explain the additional-RAM performance mechanism and one reason it is not guaranteed - correct a set of misconceptions about outputs, storage capacity, ROM and virtual storage Inside: 2 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 8 written answers. 50 marks, about 65 to 80 minutes. Series: H446 1.1.3 · Input, output and storage, part 6 of 6.
WorksheetOCR H446 1.1.3 Input, output and storage consolidation
Part 5 · H446 1.1.3 · Input, output and storage
This is the consolidation point for H446 1.1.3, worked closed-book. Two unfamiliar contexts, a set of coastal habitat stations and an analysis room with remote partner laboratories, require device selection, storage choice, memory reasoning and virtual storage to be applied together rather than one topic at a time. Students will: - design a complete input, processing and output path for a field monitoring station - justify a single device that carries two roles in the same system - recommend storage under competing constraints and set aside an irrelevant true property - diagnose common misconceptions that confuse RAM with cache or misstate the value of ROM - trace a shared remote drive to its physical media and say why it is not virtual memory Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 48 marks, about 60 to 75 minutes. Series: H446 1.1.3 · Input, output and storage, part 5 of 6.
WorksheetOCR H446 1.1.3 Virtual storage mechanism and evaluation
Part 4 · H446 1.1.3 · Input, output and storage
In H446 1.1.3, "virtual" describes how storage is presented, not the absence of hardware, and secure answers trace a local-looking drive back to physical media somewhere else. This worksheet follows that path through client software, network and remote service, then evaluates the benefits and the dependencies that come with it. Students will: - trace a request made on a local-looking drive to the remote physical media that serves it - keep virtual storage, virtual memory and virtual machines distinct from one another - explain benefits and drawbacks of virtual storage for a team working across several sites - weigh a remote-only, a local-only and a mixed design against an unreliable network - correct the claim that virtual storage sits on no real physical medium Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 38 marks, about 55 to 70 minutes. Series: H446 1.1.3 · Input, output and storage, part 4 of 6.
WorksheetOCR H446 1.1.3 RAM and ROM roles and performance
Part 3 · H446 1.1.3 · Input, output and storage
RAM and ROM are easy to define and hard to apply, so H446 1.1.3 answers often stall at "RAM is temporary". This worksheet tracks both through power-on, active use and power-off, then works through the real reason additional RAM can improve performance, which is reduced reliance on virtual memory. Students will: - state what RAM and ROM hold and whether that content survives a loss of power - explain the mechanism by which additional RAM may improve performance - correct the claim that adding RAM makes the processor clock run faster - describe a use of ROM in an embedded system other than start-up code - separate RAM, ROM, cache, secondary storage and virtual memory by purpose and data movement Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 38 marks, about 55 to 70 minutes. Series: H446 1.1.3 · Input, output and storage, part 3 of 6.
WorksheetOCR H446 1.1.3 Magnetic, flash and optical storage selection
Part 2 · H446 1.1.3 · Input, output and storage
Storage questions in H446 1.1.3 are about the type of storage, not the make of device, so an answer naming a USB stick has not yet answered the question. This worksheet separates magnetic, flash and optical storage from the devices that use them, and builds recommendations that run from a stated constraint to a relevant property to a contextual consequence. Students will: - distinguish magnetic, flash and optical storage from the devices built on them - match a stated constraint to the storage property that actually decides the choice - recommend a storage type for archive, portable and low-cost distribution needs - compare competing designs on speed, capacity, cost and failure risk - rewrite a device-level answer as a type-level one and qualify the recommendation Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 34 marks, about 50 to 65 minutes. Series: H446 1.1.3 · Input, output and storage, part 2 of 6.
WorksheetOCR H446 1.1.3 Device roles and contextual selection
Part 1 · H446 1.1.3 · Input, output and storage
OCR H446 1.1.3 does not ask for the internal workings of a device, it asks students to pick one that fits the situation and say why. This worksheet builds that habit by classifying input, output and storage devices by the role they play in the flow of data, then justifying each choice from the exact data captured or effect produced. Students will: - classify a device as input, output or storage by the role it plays in a system - name the exact data captured or the effect produced by a chosen device - recommend an input and an output device for a described user and environment - explain why a technically true statement about a device can still be a poor recommendation - justify device choices in unfamiliar contexts, including noisy and weather-exposed settings Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 28 marks, about 40 to 55 minutes. Series: H446 1.1.3 · Input, output and storage, part 1 of 6.
WorksheetOCR H446 1.1.2 Types of processor exam transition
Part 5 · H446 1.1.2 · Types of processor
Closed-book assessment for OCR H446 1.1.2, written in original contexts to test whether the processor models hold up without prompts. It runs from matched CISC and RISC comparison through workload classification and core scheduling to an extended judgement on a research vehicle with mixed processing hardware. Students will: - compare three CISC and RISC differences under examination conditions with claims qualified - justify a processor route where battery life and software compatibility pull in opposite directions - recommend CPU, GPU or mixed processing for several contrasting workloads - explain a two core schedule and why doubling the cores does not halve the time - discuss processor choices across control, image processing, modelling and existing software in one extended response Inside: 2 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 7 written answers. 50 marks, about 65 to 80 minutes. Series: H446 1.1.2 · Types of processor, part 5 of 5.
WorksheetOCR H446 1.1.2 Types of processor consolidation
Part 4 · H446 1.1.2 · Types of processor
Two unfamiliar applied contexts, a mobile mapping platform and a flood simulation service, carry the consolidation of OCR H446 1.1.2. Students begin with closed-book retrieval and then apply CISC and RISC comparison, CPU and GPU choice and parallel allocation without returning to the worked examples. Students will: - reach a qualified processor recommendation for a low power terminal tied to legacy software - split a workflow between CPU, GPU and mixed processing according to workload shape - schedule a staged job on two cores and then on four - identify the serial stages and the storage bottleneck that cap a speed-up - repair claims that confuse parallel processing with pipelining or assume gain in proportion to cores Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 46 marks, about 55 to 70 minutes. Series: H446 1.1.2 · Types of processor, part 4 of 5.
WorksheetOCR H446 1.1.2 Multicore and parallel systems
Part 3 · H446 1.1.2 · Types of processor
Adding cores rarely divides the running time, and OCR H446 1.1.2 expects students to explain why not. Using a task graph with serial stages at each end, this worksheet allocates work across cores and then works through the software, dependency and bottleneck reasons the gain falls short, keeping parallel processing clearly apart from pipelining. Students will: - allocate only the tasks that are ready to run to the available processing units - describe a valid schedule on two cores and say how it changes with three - explain why a serial stage cannot run alongside the tasks that depend on it - give software, dependency and system bottleneck reasons for a disappointing speed-up - compare multiple processors, multiple cores and a GPU for one scientific workload Inside: 7 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 42 marks, about 60 to 75 minutes. Series: H446 1.1.2 · Types of processor, part 3 of 5.
WorksheetOCR H446 1.1.2 GPU workloads, SIMD and uses
Part 2 · H446 1.1.2 · Types of processor
A GPU recommendation only earns marks in OCR H446 1.1.2 when the workload justifies it, so this worksheet starts from the shape of the work rather than the label on the device. Students classify workloads, follow one operation across many independent data items, and then test the model against a case where a very large data set is still the wrong fit. Students will: - describe the kind of work a CPU suits and the kind a GPU suits - identify the repeated operation and the independent data items in a workload - choose CPU, GPU or a mixed design for a stated task and justify it - connect concurrent processing to a visible or timing consequence in an interactive simulation - explain why a large but dependency-heavy data set does not justify a GPU Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 38 marks, about 50 to 65 minutes. Series: H446 1.1.2 · Types of processor, part 2 of 5.
WorksheetOCR H446 1.1.2 CISC and RISC differences and uses
Part 1 · H446 1.1.2 · Types of processor
OCR H446 1.1.2 treats CISC and RISC as contrasting models rather than absolute rules about real chips, and this worksheet keeps that qualification visible throughout. Students build the instruction level difference, compare one criterion at a time, then apply the model to devices carrying genuine power and software constraints. Students will: - describe how one operation can be one complex instruction or a longer sequence of simpler ones - compare CISC and RISC using the same criterion on each side - qualify claims about cycles, pipelining and speed instead of stating them as universal rules - justify a processor choice from power, cooling and software compatibility - explain the code size and compiler consequences of the two instruction set models Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 4 written answers. 35 marks, about 55 to 70 minutes. Series: H446 1.1.2 · Types of processor, part 1 of 5.
WorksheetOCR H446 1.1.1 Processor pipeline state and schedule clinic
Part 11 · H446 1.1.1 · Structure and function of the processor
Pipelining is the part of OCR H446 1.1.1 that students can describe but not draw, so this clinic has them build the schedule itself. They construct the ideal diagonal of fetch, decode and execute, check it against stated invariants, then apply supplied dependency and branch rules to see where it breaks down. Students will: - construct an ideal fetch, decode and execute schedule for several independent instructions - check a schedule against the rules on stage order and one stage of progress per cycle - identify the precise fault in an invalid proposed cycle - apply a supplied dependency rule and show the resulting stall - evaluate a performance claim that assumes a fixed completion time for any pipelined processor Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 26 marks, about 25 to 35 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 11 of 12.
WorksheetOCR H446 1.1.1 Processor structure and function exam transition
Part 10 · H446 1.1.1 · Structure and function of the processor
This is the assessment piece for OCR H446 1.1.1, intended to be sat closed-book rather than taught from. Its original questions sample the whole specification row, running from register precision and a full fetch description to an extended evaluation of processor design choices for a live audio device. Students will: - answer processor questions with precise terminology under examination conditions - describe a fetch from a stated address and give the resulting register contents - explain how decode and execute change the processor when a branch condition is true - write one qualified account covering clock speed, cores and cache together - evaluate architecture, cache and pipelining choices for a low delay device on a moderate budget Inside: 2 explanation cells, 1 multiple-choice question and 9 written answers. 47 marks, about 55 to 70 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 10 of 12.
WorksheetOCR H446 1.1.1 Processor structure and function consolidation
Part 9 · H446 1.1.1 · Structure and function of the processor
Everything in OCR H446 1.1.1 is interleaved here in one closed-book pass, from components and registers through buses and the fetch, decode and execute cycle to performance and architecture. It is built for use after the teaching sheets, with the explanation prompts used to repair answers rather than to prevent mistakes. Students will: - retrieve register, bus and component facts with no notes to hand - describe the purpose of all three buses in a single response - explain why a taken branch changes the program counter rather than the current instruction register - account for a core upgrade that barely improves a dependent single-threaded task - evaluate a change of architecture for a low-cost device that repeatedly processes a fixed sensor stream Inside: 2 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 7 written answers. 40 marks, about 45 to 60 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 9 of 12.
WorksheetOCR H446 1.1.1 Von Neumann, Harvard and contemporary architectures
Part 8 · H446 1.1.1 · Structure and function of the processor
Comparison marks in OCR H446 1.1.1 depend on using the same criterion on both sides, which is exactly where Von Neumann and Harvard answers tend to fail. This worksheet models a matched comparison, adds broad contemporary approaches, and finishes with a justified recommendation for an unfamiliar device. Students will: - compare how Von Neumann and Harvard designs store and reach instructions and data - write a comparison that applies one shared criterion to both architectures - state a cost or complexity consequence alongside any claim about speed - explain how a supplied contemporary example goes beyond one instruction stream and one data item at a time - recommend an architecture for a stated workload and budget and justify the choice Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 3 written answers. 21 marks, about 30 to 40 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 8 of 12.
WorksheetOCR H446 1.1.1 Processor pipelining
Part 7 · H446 1.1.1 · Structure and function of the processor
Pipelining is routinely confused with having more cores, so this OCR H446 1.1.1 worksheet holds it to one idea: different instructions occupying different stages at the same time. Students move from an everyday overlap analogy to a cycle count comparison, then to the things that disrupt the ideal saving. Students will: - explain pipelining as the overlap of fetch, decode and execute across instructions - compare the cycles needed with and without overlap for a short instruction sequence - distinguish improved throughput from the time a single instruction takes - explain how a dependency between instructions reduces the saving - describe the effect on efficiency when a branch is taken after later instructions have been fetched Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 16 marks, about 20 to 30 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 7 of 12.
WorksheetOCR H446 1.1.1 CPU performance: clock, cores and cache
Part 6 · H446 1.1.1 · Structure and function of the processor
Clock speed, cores and cache only earn marks in OCR H446 1.1.1 when a mechanism and a condition come with them. This worksheet turns each feature into a causal chain, then sets it against workloads where the expected improvement does not appear, so students learn to qualify rather than assert. Students will: - explain the mechanism by which clock speed, cache and cores may change performance - say why a clock speed figure is not the number of instructions completed each second - attach a workload condition to every performance claim - compare more cores against a larger or faster cache for a stated workload - identify the bottleneck that limits the benefit of an upgrade in a given scenario Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 18 marks, about 25 to 35 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 6 of 12.
WorksheetOCR H446 1.1.1 Decode, execute and branching
Part 5 · H446 1.1.1 · Structure and function of the processor
Decode and execute are separate stages, and OCR H446 1.1.1 rewards students who can say precisely what changes in each. Working from opcodes and operands through arithmetic, comparison and branch instructions, this worksheet has students predict the processor state a supplied instruction leaves behind. Students will: - distinguish what happens during decode from what happens during execute - describe how the control unit interprets an opcode and its operand - predict the effect of a supplied arithmetic instruction on the accumulator - explain when a branch target is written to the program counter - state the final program counter value for both a taken and a not taken branch Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 16 marks, about 20 to 30 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 5 of 12.
WorksheetOCR H446 1.1.1 Fetch stage register and bus sequence
Part 4 · H446 1.1.1 · Structure and function of the processor
The fetch stage earns marks in OCR H446 1.1.1 only when it is told in order, with named registers and buses rather than a loose list of abbreviations. This worksheet rebuilds fetch as an ordered sequence of transfers and then takes the diagram away so students reconstruct it themselves. Students will: - put the transfers of the fetch stage into the order examiners expect - state the value held by a given register at a stated point in the fetch - describe the fetch stage using named registers and buses together - give the contents of MAR, MDR, CIR and PC immediately after a fetch from a stated address - rebuild the fetch sequence from memory with no diagram and no answer bank Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 19 marks, about 25 to 35 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 4 of 12.
WorksheetOCR H446 1.1.1 Data, address and control buses
Part 3 · H446 1.1.1 · Structure and function of the processor
Bus questions in OCR H446 1.1.1 are marked on what each set of lines carries and in which direction, not on naming three buses. This worksheet builds the address, data and control model on a worked memory read, then asks students to turn the same model round for a write. Students will: - state what the address, data and control buses each carry - connect the memory address register and memory data register to the bus that serves each - trace a memory read from the address leaving the processor to the value arriving back - describe the direction of travel on each bus during a memory write - explain the part two named buses play in a supplied transfer Inside: 5 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 15 marks, about 20 to 25 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 3 of 12.
WorksheetOCR H446 1.1.1 Named registers and low-level instruction bridge
Part 2 · H446 1.1.1 · Structure and function of the processor
Named registers are the vocabulary behind every state question in OCR H446 1.1.1, so this worksheet gives each of the five its full name before using the abbreviation, then tracks contents through simple low-level instructions. Assembly appears only as a readable stand-in for the binary, with each instruction meaning supplied. Students will: - state what each of the five named registers holds - identify a register from the value it currently contains - follow a supplied load, add and store sequence through MAR, MDR and the accumulator - describe the register changes caused by a single supplied instruction - explain how the contents of the program counter differ from those of the current instruction register Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 2 written answers. 14 marks, about 20 to 30 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 2 of 12.
WorksheetOCR H446 1.1.1 Control unit, ALU and processor organisation
Part 1 · H446 1.1.1 · Structure and function of the processor
OCR H446 1.1.1 expects students to separate the control unit, the ALU and the registers by what each one does or holds, and weak answers collapse all three into a vague claim that the processor "processes data". This worksheet builds that division of labour from a worked pricing calculation so every action is attributed to a named component. Students will: - distinguish the control unit from the ALU by the action each one performs - state which processor component holds a temporary value during a calculation - explain the roles of the CU and ALU in carrying out a supplied comparison instruction - say where the result of an operation may be held once it has been produced - complete component statements from memory without an answer bank Inside: 6 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 1 written answer. 12 marks, about 15 to 25 minutes. Series: H446 1.1.1 · Structure and function of the processor, part 1 of 12.
Workspace1CP2-CT-6.WS6 Turtle practical checkpoint
Part 6 · 1CP2-CT-6 · Turtle practical lessons
The practical checkpoint for the Turtle topic, where the program and the picture it makes are both the evidence. Students will: - meet a specification using subprograms and parameters - use iteration rather than repeated instructions - control colour, fill and drawing order - test the program and correct what the drawing reveals - explain the structure of the finished program A Workspace lesson: students write and run their own Python in the editor. About 60 minutes. Series: 1CP2-CT-6 · Turtle practical lessons, part 6 of 6.
Workspace1CP2-CT-6.WS5 Extended decomposed Turtle design
Part 5 · 1CP2-CT-6 · Turtle practical lessons
The extended practical lesson, where students plan a design of their own and then build it. Students will: - plan a drawing before writing any code - decompose the plan into subprograms with parameters - build and test the design one part at a time - refine the drawing after seeing the result - keep the finished program readable and commented A Workspace lesson: students write and run their own Python in the editor. About 90 minutes. Series: 1CP2-CT-6 · Turtle practical lessons, part 5 of 6.
Workspace1CP2-CT-6.WS4 Compose a scene with subprograms and layers
Part 4 · 1CP2-CT-6 · Turtle practical lessons
The fourth practical lesson, composing a whole scene from subprograms drawn in a deliberate order. Students will: - decompose a scene into named subprograms - use parameters to place and size each object - choose a drawing order so layers appear correctly - test each subprogram before composing the scene - correct a scene whose layers were drawn in the wrong order A Workspace lesson: students write and run their own Python in the editor. About 60 minutes. Series: 1CP2-CT-6 · Turtle practical lessons, part 4 of 6.
Workspace1CP2-CT-6.WS3 Pen colour fill and circles
Part 3 · 1CP2-CT-6 · Turtle practical lessons
The third practical lesson, adding colour, fill and curves to the shapes students can already draw. Students will: - set pen colour and pen width - fill a closed shape - draw whole circles and arcs - combine colour and fill in one drawing - keep a program readable as it grows A Workspace lesson: students write and run their own Python in the editor. About 60 minutes. Series: 1CP2-CT-6 · Turtle practical lessons, part 3 of 6.
Workspace1CP2-CT-6.WS2 Coordinates polygons and reusable shapes
Part 2 · 1CP2-CT-6 · Turtle practical lessons
The second practical lesson, moving from single lines to closed shapes drawn by iteration. Students will: - move to a coordinate before starting to draw - draw a regular polygon using a loop - calculate the turn angle a polygon needs - turn a repeated shape into a reusable subprogram - draw the same shape in more than one place A Workspace lesson: students write and run their own Python in the editor. About 60 minutes. Series: 1CP2-CT-6 · Turtle practical lessons, part 2 of 6.
Workspace1CP2-CT-6.WS1 First Turtle lines and state
Part 1 · 1CP2-CT-6 · Turtle practical lessons
The first practical Turtle lesson, where students run their own program and watch the drawing appear. Students will: - set up a Turtle program and run it - move and turn the Turtle deliberately - raise and lower the pen to move without drawing - keep track of position, direction and pen state - change one instruction at a time and observe the effect A Workspace lesson: students write and run their own Python in the editor. About 60 minutes. Series: 1CP2-CT-6 · Turtle practical lessons, part 1 of 6.
Worksheet1CP2-P-9.6 Bitmap sound and compression checkpoint
Part 6 · 1CP2-P-9 · Bitmap, sound and compression
This checkpoint assesses P-9 only. Show formulae, working and units. Keep pixel dimensions separate from bit size, and sample rate separate from sample interval. Students will: - apply bitmap and sound size calculations with working and units - keep dimensions separate from storage size - explain sampling and colour-depth effects - recommend compression from the need for exact reconstruction Inside: 3 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions and 6 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-9 · Bitmap, sound and compression, part 6 of 6.
Worksheet1CP2-P-9.5 Lossless and lossy compression
Part 5 · 1CP2-P-9 · Bitmap, sound and compression
Compression reduces the number of bits used to store or transmit data. Lossless compression allows the original to be reconstructed exactly. Lossy compression permanently removes or approximates information to achieve a smaller representation. Students will: - distinguish lossless from lossy compression - use exact reconstruction as a selection criterion - explain why compression can reduce transfer time - recommend an approach for a stated context Inside: 7 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 12 marks, about 45 minutes. Series: 1CP2-P-9 · Bitmap, sound and compression, part 5 of 6.
Worksheet1CP2-P-8.5 Environment languages and intellectual property checkpoint
Part 5 · 1CP2-P-8 · Environment, languages and intellectual property
This checkpoint assesses P-8 only. Use precise characteristics, linked cause-and-consequence reasoning and contextual decisions. It introduces no new legislation or translator type. Students will: - link environmental causes to developed consequences - compare language levels and translation workflows - apply intellectual-property and licensing concepts - build a precise contextual judgement Inside: 3 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-8 · Environment, languages and intellectual property, part 5 of 5.
Worksheet1CP2-P-10.5 AI personal data and ethical legal issues checkpoint
Part 5 · 1CP2-P-10 · AI, personal data and ethical/legal issues
This final principles checkpoint assesses AI/ML/robotics, accountability, safety, bias, liability, personal-data collection, privacy, misuse and data-protection principles. Accurate mechanism comes before judgement. Students will: - explain AI and machine-learning mechanisms accurately - connect bias, safety and accountability to consequences - apply personal-data and privacy principles - plan a developed ethical and legal discussion Inside: 3 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-10 · AI, personal data and ethical/legal issues, part 5 of 5.
Worksheet1CP2-CT-8.5 Tracing debugging sorting and searching checkpoint
Part 5 · 1CP2-CT-8 · Tracing, debugging, sorting and searching
This checkpoint assesses the CT-8 series only. Recall: a trace records changed state in execution order; syntax, runtime and logic errors differ; bubble sort compares adjacent items; binary search requires sorted data and discards half of its remaining range. Students will: - complete a formal trace with reduced support - apply bubble sort and binary search by hand - diagnose a logic error from evidence - amend and retest a search program Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions, 1 trace table, 5 written answers and 1 Python task. 20 marks, about 45 minutes. Series: 1CP2-CT-8 · Tracing, debugging, sorting and searching, part 5 of 5.
Worksheet1CP2-CT-10.5 Final computational thinking and programming checkpoint
Part 5 · 1CP2-CT-10 · Integrated programming and data structures
This is the collection's Paper 2 transition. It samples two-dimensional data, subprogram interfaces, testing, tracing and correction. Read each requirement carefully; exact output and returned values are different demands. Students will: - decompose an integrated programming requirement - trace two-dimensional data and subprogram state - design tests with explicit expected results - write and reason about a complete PLS-compatible solution Inside: 3 explanation cells, 1 fill-in-the-blanks cell, 5 written answers, 1 trace table, 1 Python task and 1 multiple-choice question. 20 marks, about 45 minutes. Series: 1CP2-CT-10 · Integrated programming and data structures, part 5 of 5.
Worksheet1CP2-P-9.4 Sound file size and fidelity trade-offs
Part 4 · 1CP2-P-9 · Bitmap, sound and compression
For mono uncompressed sound, size in bits is sample rate × bit depth × duration in seconds. The units are samples/second × bits/sample × seconds, leaving bits. Students will: - construct the uncompressed sound-size expression - calculate in bits, bytes and binary storage units - rearrange the expression to find duration - explain fidelity and storage trade-offs precisely Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 13 marks, about 45 minutes. Series: 1CP2-P-9 · Bitmap, sound and compression, part 4 of 6.
Worksheet1CP2-P-8.4 Intellectual property and software licensing
Part 4 · 1CP2-P-8 · Environment, languages and intellectual property
Intellectual property (IP) covers creations of the mind and legal rights connected to them. Software source code is normally protected by copyright. A licence states how someone may install, use, copy, modify or redistribute software. Buying access does not automatically transfer copyright ownership. Students will: - separate copyright, patents, trademarks and licences - interpret what a software licence permits - distinguish owning a copy from owning copyright - apply intellectual-property concepts to scenarios Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 4 written answers. 15 marks, about 45 minutes. Series: 1CP2-P-8 · Environment, languages and intellectual property, part 4 of 5.
Worksheet1CP2-P-10.4 Privacy ownership misuse and data protection
Part 4 · 1CP2-P-10 · AI, personal data and ethical/legal issues
Privacy concerns a person's control and reasonable expectations around information and life. Data use can raise ethical questions about ownership or control and legal duties about processing. UK data-protection teaching at GCSE should focus on stable principles, not statute sections or volatile procedural detail. Students will: - distinguish privacy, ownership, misuse and legal duties - apply stable data-protection principles across a lifecycle - separate ethical concerns from legal requirements - audit and improve a fictional data practice Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 14 marks, about 45 minutes. Series: 1CP2-P-10 · AI, personal data and ethical/legal issues, part 4 of 5.
Worksheet1CP2-CT-9.4 Test trace debug and search checkpoint
Part 4 · 1CP2-CT-9 · Testing, structures and integrated solutions
This checkpoint assesses CT-9 and retrieves the formal methods needed to use it. It introduces no new list, file, trace or error technique. Students will: - select tests with inputs, expected results and reasons - trace list traversal and search state - diagnose a defect from its observed behaviour - amend and test a complete search without unsupported shortcuts Inside: 4 explanation cells, 1 fill-in-the-blanks cell, 4 written answers, 1 trace table, 2 multiple-choice questions and 1 Python task. 19 marks, about 45 minutes. Series: 1CP2-CT-9 · Testing, structures and integrated solutions, part 4 of 4.
Worksheet1CP2-CT-8.4 Binary search halving sorted data
Part 4 · 1CP2-CT-8 · Tracing, debugging, sorting and searching
Binary search finds an item in sorted data. It compares the target with the middle item. If they are unequal, it discards the half that cannot contain the target. This repeated halving is a divide-and-conquer method. Students will: - apply binary search only to sorted data - update lower and upper bounds after each comparison - trace a complete search systematically - repair a boundary update that fails to shrink the range Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions, 4 written answers and 1 trace table. 16 marks, about 45 minutes. Series: 1CP2-CT-8 · Tracing, debugging, sorting and searching, part 4 of 5.
Worksheet1CP2-CT-10.4 Test trace debug and refine an integrated program
Part 4 · 1CP2-CT-10 · Integrated programming and data structures
Refinement is evidence-led. Translate requirements into expected behaviour and design tests. Trace a failure, locate its cause and amend the code. Then rerun both the failing test and earlier regression tests. Correctness, readability and efficiency are separate qualities. Students will: - turn requirements into expected test behaviour - trace an integrated program to locate a defect - amend code while preserving correct behaviour - rerun failing and regression tests after refinement Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 4 written answers, 2 multiple-choice questions, 1 trace table and 1 Python task. 20 marks, about 45 minutes. Series: 1CP2-CT-10 · Integrated programming and data structures, part 4 of 5.
Worksheet1CP2-P-9.3 Sampling analogue sound into binary
Part 3 · 1CP2-P-9 · Bitmap, sound and compression
Sound in air varies continuously. A microphone produces an analogue signal. An analogue-to-digital process measures amplitude at regular times, rounds each measurement to an available level and stores the level as a binary code. Students will: - describe sampling from an analogue signal into binary - distinguish sample rate from sample interval - explain how sample rate and bit depth affect representation - order the stages of analogue-to-digital conversion Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 12 marks, about 45 minutes. Series: 1CP2-P-9 · Bitmap, sound and compression, part 3 of 6.
Worksheet1CP2-P-8.3 Compilers interpreters and translation
Part 3 · 1CP2-P-8 · Environment, languages and intellectual property
A processor cannot directly execute high-level source code. A compiler translates the whole program and normally produces executable object code before it runs. An interpreter translates and executes source statements during each run. Both can report errors; their workflow differs. Students will: - distinguish source code, object code and machine code - compare compiler and interpreter workflows - separate translation characteristics from possible advantages - choose and justify a translator for a context Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 4 written answers. 14 marks, about 45 minutes. Series: 1CP2-P-8 · Environment, languages and intellectual property, part 3 of 5.
Worksheet1CP2-P-10.3 Personal data collection consent and digital footprints
Part 3 · 1CP2-P-10 · AI, personal data and ethical/legal issues
Personal data identifies or relates to an identifiable living person. It includes more than names: identifiers, location, account activity and combinations of facts may identify someone. A digital footprint can be active, such as posting, or passive, such as logged device activity. Students will: - identify personal data beyond obvious names - distinguish active and passive digital footprints - evaluate purpose, consent and proportionality - recommend safer data collection in context Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 14 marks, about 45 minutes. Series: 1CP2-P-10 · AI, personal data and ethical/legal issues, part 3 of 5.
Worksheet1CP2-CT-9.3 Files strings lists and subprograms integrated solution
Part 3 · 1CP2-CT-9 · Testing, structures and integrated solutions
Integrated programs are easier to reason about when decomposed. This worksheet uses a fictional CSV schema name,score, for example Asha,17. File input produces strings, so numeric score text must be converted before arithmetic or comparison. Students will: - follow data from a CSV file into converted list values - decompose processing into a focused subprogram - calculate and return a result from supplied records - design tests for the integrated solution Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions, 3 written answers and 1 Python task. 19 marks, about 45 minutes. Series: 1CP2-CT-9 · Testing, structures and integrated solutions, part 3 of 4.
Worksheet1CP2-CT-8.3 Bubble sort passes swaps and comparisons
Part 3 · 1CP2-CT-8 · Tracing, debugging, sorting and searching
Bubble sort repeatedly compares neighbouring items. If a pair is in the wrong order, it swaps them. One complete pass moves the largest remaining item towards the end. Passes repeat until a pass makes no swaps. You must apply, trace, recognise and amend this method; the specification does not require a full blank-editor implementation. Students will: - apply bubble sort one complete pass at a time - record comparisons, swaps and resulting list states - recognise bubble sort in Python - amend a faulty comparison and explain its effect Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions and 5 written answers. 17 marks, about 45 minutes. Series: 1CP2-CT-8 · Tracing, debugging, sorting and searching, part 3 of 5.
Worksheet1CP2-CT-10.3 From CSV file to structured solution
Part 3 · 1CP2-CT-10 · Integrated programming and data structures
The supplied clubs.csv uses the schema name,club,score, for example Asha,Robotics,68. Reading produces text. The loader must split each line, convert score to integer and append one typed row to a two-dimensional list. Students will: - load and convert records from the supplied CSV file - decompose file, structure and processing stages - write a parameterised function over typed rows - format and test the required result Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions, 3 written answers and 1 Python task. 19 marks, about 45 minutes. Series: 1CP2-CT-10 · Integrated programming and data structures, part 3 of 5.
Worksheet1CP2-P-9.2 Bitmap file size and quality trade-offs
Part 2 · 1CP2-P-9 · Bitmap, sound and compression
Uncompressed bitmap size in bits is width × height × colour depth. Width and height are measured in pixels; colour depth is bits per pixel, so pixel units cancel and leave bits. Students will: - construct the bitmap file-size expression - calculate in bits, bytes and binary storage units - rearrange the expression to find a missing dimension - explain quality and storage trade-offs precisely Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 13 marks, about 45 minutes. Series: 1CP2-P-9 · Bitmap, sound and compression, part 2 of 6.
Worksheet1CP2-P-8.2 High-level and low-level programming languages
Part 2 · 1CP2-P-8 · Environment, languages and intellectual property
A high-level language uses abstractions and syntax closer to human problem descriptions. A low-level language is closer to processor instructions and hardware organisation. These are relative levels; neither is automatically best for every task. Students will: - compare high-level and low-level language characteristics - connect abstraction and hardware access to project requirements - avoid absolute claims about speed or difficulty - justify a language level for a stated task Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions and 3 written answers. 15 marks, about 45 minutes. Series: 1CP2-P-8 · Environment, languages and intellectual property, part 2 of 5.
Worksheet1CP2-P-10.2 Accountability safety bias and legal liability in AI systems
Part 2 · 1CP2-P-10 · AI, personal data and ethical/legal issues
AI outputs can influence real decisions, so people and organisations remain responsible for design, deployment and oversight. Algorithmic bias is a systematic unfair tendency caused by data or design; it is not a computer having an opinion and not every isolated wrong result. Students will: - explain how data or design can produce systematic bias - identify accountability and safety responsibilities - connect an AI output to stakeholder impact - develop a balanced discussion with practical safeguards Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-10 · AI, personal data and ethical/legal issues, part 2 of 5.
Worksheet1CP2-CT-9.2 One-dimensional structures reverse traversal and efficiency
Part 2 · 1CP2-CT-9 · Testing, structures and integrated solutions
A one-dimensional list stores an ordered sequence under one name. The first index is 0 and the last is len(values) - 1. Traversing backwards changes visit order; it does not sort or reverse the stored list. Students will: - traverse a one-dimensional structure in reverse order - predict changing indexes and output before execution - reason about efficiency from the work performed - construct a PLS-compatible reverse traversal Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions, 3 written answers, 1 trace table and 1 Python task. 14 marks, about 45 minutes. Series: 1CP2-CT-9 · Testing, structures and integrated solutions, part 2 of 4.
Worksheet1CP2-CT-8.2 Diagnosing and correcting program errors
Part 2 · 1CP2-CT-8 · Tracing, debugging, sorting and searching
A syntax error breaks the language rules, so the code cannot be translated or started normally. A runtime error occurs while syntactically valid code executes an operation that cannot be completed. A logic error allows the program to run but produces incorrect behaviour. Runtime does not mean ‘slow’. Students will: - distinguish syntax, runtime and logic errors from evidence - locate and explain a boundary fault - amend a program rather than only naming its error - choose tests that demonstrate the repair Inside: 7 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions, 3 written answers and 1 Python task. 18 marks, about 45 minutes. Series: 1CP2-CT-8 · Tracing, debugging, sorting and searching, part 2 of 5.
Worksheet1CP2-CT-10.2 Traversing displaying and searching two-dimensional data
Part 2 · 1CP2-CT-10 · Integrated programming and data structures
An outer loop selects each record. Direct field indexing or an inner loop accesses fields inside that record. For a search, compare only the named key field and preserve the complete matched row when the requirement asks for the record. Students will: - traverse records and their fields systematically - predict nested traversal before execution - search using the named key field - construct a search that preserves the complete matched row Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions, 4 written answers, 1 trace table and 1 Python task. 19 marks, about 45 minutes. Series: 1CP2-CT-10 · Integrated programming and data structures, part 2 of 5.
Worksheet1CP2-P-9.1 Bitmap images pixels resolution and colour depth
Part 1 · 1CP2-P-9 · Bitmap, sound and compression
A bitmap stores an image as a rectangular grid of pixels. Each pixel position stores a binary colour code. Width × height gives the number of pixels; it does not give file size. Students will: - explain how pixels and colour codes form a bitmap - calculate pixel counts and available colours - distinguish image dimensions from storage size - encode and decode a small monochrome bitmap Inside: 7 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 4 written answers. 15 marks, about 45 minutes. Series: 1CP2-P-9 · Bitmap, sound and compression, part 1 of 6.
Worksheet1CP2-P-8.1 Environmental impacts across a device lifecycle
Part 1 · 1CP2-P-8 · Environment, languages and intellectual property
Computing devices affect the environment before, during and after use. A developed examination answer links a specific activity to an environmental change and then to a consequence. Merely writing ‘pollution’ or ‘bad for the environment’ is too vague. Students will: - connect each device lifecycle stage to an environmental consequence - distinguish manufacture, use and disposal impacts - match practical mitigations to the harm they address - make a balanced recommendation in context Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions and 3 written answers. 14 marks, about 45 minutes. Series: 1CP2-P-8 · Environment, languages and intellectual property, part 1 of 5.
Worksheet1CP2-P-10.1 Artificial intelligence machine learning and robotics
Part 1 · 1CP2-P-10 · AI, personal data and ethical/legal issues
Artificial intelligence (AI) describes systems carrying out tasks associated with intelligent behaviour. Machine learning (ML) is an AI approach that learns patterns from data instead of receiving every decision rule explicitly. Robotics concerns programmable physical machines that sense or act. The categories can overlap without being identical. Students will: - distinguish artificial intelligence, machine learning and robotics - connect sensor input, processing and physical action - classify systems without treating the terms as interchangeable - explain a mechanism in a stated application Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 2 multiple-choice questions and 3 written answers. 13 marks, about 45 minutes. Series: 1CP2-P-10 · AI, personal data and ethical/legal issues, part 1 of 5.
Worksheet1CP2-CT-9.1 Designing test data and validating behaviour
Part 1 · 1CP2-CT-9 · Testing, structures and integrated solutions
A test case contains input data, an expected result and a reason. Choose expected results before running the program. Normal valid data checks typical behaviour; boundary data checks exact limits and values just around them; erroneous data violates a requirement and should be rejected. Students will: - derive normal, boundary and erroneous tests from requirements - state an expected result before running a program - test compound validation rules systematically - repair validation and rerun relevant tests Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions, 2 written answers and 1 Python task. 17 marks, about 45 minutes. Series: 1CP2-CT-9 · Testing, structures and integrated solutions, part 1 of 4.
Worksheet1CP2-CT-8.1 Formal trace tables and variable state
Part 1 · 1CP2-CT-8 · Tracing, debugging, sorting and searching
A trace table records how an algorithm's state changes while it runs. Examiners use traces to check that you can follow sequence, selection and iteration systematically. A trace is evidence, not a guess at the final output. Students will: - record changing state, conditions and output in execution order - complete a formal trace without treating blanks as zero - distinguish a stored value from printed output - explain evidence from a trace precisely Inside: 6 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions, 3 written answers and 1 trace table. 12 marks, about 45 minutes. Series: 1CP2-CT-8 · Tracing, debugging, sorting and searching, part 1 of 5.
Worksheet1CP2-CT-10.1 Records rows fields and two-dimensional structures
Part 1 · 1CP2-CT-10 · Integrated programming and data structures
A two-dimensional structure stores rows containing related fields. In Python's PLS representation, it is a list of lists. The first index selects a row; the second selects a field inside that row. Students will: - represent related fields as typed rows - use the first index for a row and the second for a field - preserve the meaning and type of each field - trace reads from a two-dimensional structure Inside: 5 explanation cells, 1 fill-in-the-blanks cell, 3 multiple-choice questions, 3 written answers and 1 trace table. 12 marks, about 45 minutes. Series: 1CP2-CT-10 · Integrated programming and data structures, part 1 of 5.
Worksheet1CP2-P-6.8 Networks checkpoint
Part 8 · 1CP2-P-6 · Networks
The checkpoint for the whole networks series, sampling LAN and WAN, the internet, performance, media and topologies. Students will: - explain two differences between a LAN and a WAN - describe how DNS, IP addresses and routers deliver a request - construct a transmission-time expression with correct conversions - explain fibre transmission and one advantage over copper - give one advantage and one disadvantage of replacing wired with wireless Inside: 2 explanation cells, 1 multiple-choice question and 9 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 8 of 8.
Worksheet1CP2-CT-2.8 Selection and while-loop checkpoint
Part 8 · 1CP2-CT-2 · Selection, strings and while loops
The checkpoint for the whole series, sampling strings, selection and while loops in one integrated task. Students will: - use string methods accurately and say what they leave unchanged - write a condition for an inclusive range - correct a wrongly ordered selection chain - state the complete output and final value of a loop - write an integrated program and choose a boundary test for it Inside: 7 explanation cells, 2 multiple-choice questions, 1 Python task, 2 fill-in-the-blanks cells and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 8 of 8.
Worksheet1CP2-P-6.7 Bus star and mesh topologies
Part 7 · 1CP2-P-6 · Networks
The topology worksheet, reading each arrangement and then explaining the consequences it has for reliability. Students will: - identify bus, star and mesh from a description - explain two disadvantages of a bus topology - give a reliability advantage and disadvantage of a star - explain why a partial mesh suits a service that must keep running - select a topology from stated growth and reliability requirements Inside: 7 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 7 of 8.
Worksheet1CP2-CT-5.7 Merge sort file handling and authentication checkpoint
Part 7 · 1CP2-CT-5 · Merge sort, files and authentication
The checkpoint for the whole series, sampling merge sort, file modes and authentication in one sitting. Students will: - identify the first pairwise merge stage of a list - explain why a merge needs remainder handling - explain why a converted field calculates rather than concatenates - distinguish write mode from append mode with a suitable use of each - write an authentication routine and choose tests that grant and deny Inside: 4 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-5 · Merge sort, files and authentication, part 7 of 7.
Worksheet1CP2-P-4.7 Operating systems and utilities checkpoint
Part 7 · 1CP2-P-4 · Operating systems and utilities
The checkpoint for the whole series, sampling OS responsibilities, permissions and every utility the series covered. Students will: - summarise what an operating system is for - describe process and memory management under limited resources - explain how authentication and permissions combine for temporary access - recommend a backup, compression, maintenance and detection approach - correct two common utility misconceptions Inside: 3 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-4 · Operating systems and utilities, part 7 of 7.
Worksheet1CP2-CT-4.7 Formatting structures validation and search checkpoint
Part 7 · 1CP2-CT-4 · Structures, validation and search
The checkpoint for the whole series, integrating formatting, structures, validation and search. Students will: - choose the format descriptor a stated presentation requires - explain both indexes of a two-dimensional read - describe a validation routine including its control structure - state the comparisons a complete search of an absent target makes - write an integrated program and correct a fixed-row search error Inside: 4 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 3 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-4 · Structures, validation and search, part 7 of 7.
Worksheet1CP2-P-3.7 Architecture and storage checkpoint
Part 7 · 1CP2-P-3 · Architecture and storage
The checkpoint for the whole series, sampling the stored-program concept, the cycle, addressing and storage selection. Students will: - identify the feature central to the stored-program concept - describe the fetch-decode-execute cycle including registers and buses - explain a clock-speed performance claim precisely - calculate addressable locations and the resulting capacity - give a linked storage justification rather than a vague claim Inside: 7 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-3 · Architecture and storage, part 7 of 7.
Worksheet1CP2-CT-3.7 Lists iteration and subprograms checkpoint
Part 7 · 1CP2-CT-3 · Lists, iteration and subprograms
The checkpoint for the whole series, integrating lists, iteration and subprograms in one design. Students will: - choose a suitable subprogram design for a stated requirement - trace an integrated algorithm through a function call - explain why a function generalises to data of a different length - diagnose an invalid index and give two valid repairs - write an integrated program and justify its use of parameters Inside: 6 explanation cells, 2 multiple-choice questions, 1 Python task, 1 trace table, 1 fill-in-the-blanks cell and 3 written answers. 19 marks, about 45 minutes. Series: 1CP2-CT-3 · Lists, iteration and subprograms, part 7 of 7.
Worksheet1CP2-P-2.7 Signed data and encoding checkpoint
Part 7 · 1CP2-P-2 · Signed data and encoding
The checkpoint for the whole series, sampling two's complement, shifts, hexadecimal and character encoding together. Students will: - interpret and represent 8-bit two's complement patterns - apply both a logical and an arithmetic shift correctly - explain the precision consequences of each shift type - convert between binary and hexadecimal and justify the notation - explain why 7-bit ASCII cannot serve a worldwide database Inside: 6 explanation cells, 1 multiple-choice question, 5 number cells, 1 fill-in-the-blanks cell and 3 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-2 · Signed data and encoding, part 7 of 7.
Worksheet1CP2-CT-2.7 Constructing and debugging while loops
Part 7 · 1CP2-CT-2 · Selection, strings and while loops
The construction worksheet, where students choose a loop pattern from the requirement and then build it. Students will: - choose between a counting loop and a sentinel loop - construct a counting loop that stops at the right value - construct a sentinel loop that does not process its stop value - identify and correct an off-by-one loop condition - combine repetition with selection in one program Inside: 8 explanation cells, 1 multiple-choice question, 3 Python tasks, 1 fill-in-the-blanks cell and 2 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 7 of 8.
Worksheet1CP2-CT-1.7 Programming foundations checkpoint
Part 7 · 1CP2-CT-1 · Programming foundations
The checkpoint for the whole Programming foundations series, drawing the six worksheets together into one integrated task. Students will: - restate algorithms, sequence and the IPO model accurately - apply decomposition and abstraction to a new system - use named storage and the correct types - diagnose an input conversion fault and give the amendment - write an integrated program and judge the evidence its tests provide Inside: 9 explanation cells, 1 multiple-choice question, 1 Python task, 3 fill-in-the-blanks cells and 2 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-1 · Programming foundations, part 7 of 7.
Worksheet1CP2-P-7.6 Embedded systems IoT and TCP IP checkpoint
Part 6 · 1CP2-P-7 · Embedded systems, IoT and TCP/IP
The checkpoint for the whole principles topic 7 series, sampling embedded systems, the Internet of Things, packet switching and TCP/IP. Students will: - define an embedded system and distinguish it from a general-purpose computer - describe the path from a sensor reading to an actuator response - state the information a packet header carries - explain how different routes still deliver one reconstructed message - name a protocol for each stated purpose and place it at its layer Inside: 2 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 8 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-7 · Embedded systems, IoT and TCP/IP, part 6 of 6.
Worksheet1CP2-P-6.6 Wireless connections and choosing media
Part 6 · 1CP2-P-6 · Networks
The wireless worksheet, matching Wi-Fi, Bluetooth, NFC and Zigbee to the purposes each one suits. Students will: - state accurately what a wireless LAN provides - match a wireless technology to a stated purpose - compare wired and wireless connections for a fixed room - justify a low-power technology for small frequent readings - choose suitable connectivity for two contrasting cases Inside: 6 explanation cells, 4 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 6 of 8.
Worksheet1CP2-P-5.6 Cybersecurity and robust software checkpoint
Part 6 · 1CP2-P-5 · Cyber security and robust software
The checkpoint for the whole series, sampling malware, vulnerabilities, social engineering, protection and robust software. Students will: - identify a social-engineering technique from a scenario - explain how unpatched software leads to loss or disruption - recommend and justify three distinct controls for a school - compare audit trails with code reviews as methods of identifying misuse - correct two common protection misconceptions Inside: 3 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-5 · Cyber security and robust software, part 6 of 6.
Worksheet1CP2-CT-5.6 Authentication with ID and password lookup
Part 6 · 1CP2-CT-5 · Merge sort, files and authentication
The authentication worksheet, matching a credential pair on the same record rather than anywhere in the file. Students will: - keep validation and authentication distinct - explain why matching fields independently is insecure - implement a lookup that compares both fields of one record - describe the stages of authenticating against an accounts file - give three authentication tests with expected outcomes Inside: 7 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 3 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-5 · Merge sort, files and authentication, part 6 of 7.
Worksheet1CP2-P-4.6 Defragmentation and anti-malware utilities
Part 6 · 1CP2-P-4 · Operating systems and utilities
The maintenance worksheet, distinguishing a fragmentation problem from a malware problem and choosing the right utility for each. Students will: - say which storage technology defragmentation suits - explain how defragmentation reduces file access time - compare signature detection with behaviour detection - give one strength or limitation of each detection approach - apply the correct utility to each fault in a scenario Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 19 marks, about 45 minutes. Series: 1CP2-P-4 · Operating systems and utilities, part 6 of 7.
Worksheet1CP2-CT-4.6 Linear search through records
Part 6 · 1CP2-CT-4 · Structures, validation and search
The record search worksheet, comparing one field while returning another. Students will: - compare a key field within each record - explain why the search compares one field and prints another - construct a record search that handles an absent target - give a normal, a boundary and an absent test with expected results - explain why every record must share the same field positions Inside: 6 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 2 written answers. 16 marks, about 45 minutes. Series: 1CP2-CT-4 · Structures, validation and search, part 6 of 7.
Worksheet1CP2-P-3.6 Secondary storage technologies and selection
Part 6 · 1CP2-P-3 · Architecture and storage
The storage worksheet, comparing the three technologies against explicit criteria and then choosing between them. Students will: - describe how magnetic, solid-state and optical media store bits - compare technologies using speed and physical durability - select and justify a technology from the requirements of a scenario - construct an expression for a total storage requirement - evaluate a broad claim such as always choosing the fastest drive Inside: 7 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 19 marks, about 45 minutes. Series: 1CP2-P-3 · Architecture and storage, part 6 of 7.
Worksheet1CP2-CT-3.6 Functions and return values
Part 6 · 1CP2-CT-3 · Lists, iteration and subprograms
The function worksheet, and the distinction between returning a value and printing one. Students will: - follow a returned value through the program that called it - use a returned value in more than one way - complete a function that performs a pure calculation - explain why return suits a calculation better than print - state what happens when a return statement is reached Inside: 7 explanation cells, 3 multiple-choice questions, 2 Python tasks, 1 fill-in-the-blanks cell and 2 written answers. 19 marks, about 45 minutes. Series: 1CP2-CT-3 · Lists, iteration and subprograms, part 6 of 7.
Worksheet1CP2-P-2.6 Character sets and 7-bit ASCII
Part 6 · 1CP2-P-2 · Signed data and encoding
The character set worksheet, following the route from character to code to binary and back. Students will: - explain how a character becomes a code and then a binary pattern - derive nearby ASCII codes using the alphabetic offset - connect character codes to what a short Python listing outputs - state one limitation of 7-bit ASCII - recommend and justify an encoding for names in many scripts Inside: 7 explanation cells, 3 multiple-choice questions, 1 number cell, 1 fill-in-the-blanks cell and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-2 · Signed data and encoding, part 6 of 7.
Worksheet1CP2-CT-2.6 Understanding condition-controlled while loops
Part 6 · 1CP2-CT-2 · Selection, strings and while loops
The reading worksheet for condition-controlled loops, taken one complete pass at a time before any are written. Students will: - identify the three parts every while loop needs - trace a loop pass by pass and state every output - say when a pre-condition loop executes zero times - diagnose a non-terminating loop and give the fixing line - predict the final output of a loop from its listing Inside: 7 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 17 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 6 of 8.
Worksheet1CP2-CT-1.6 From sequence flowchart to Python
Part 6 · 1CP2-CT-1 · Programming foundations
The translation worksheet, connecting the flowchart notation to the Python written beside it. Students will: - map each flowchart symbol to the behaviour it stands for in code - follow a reliable method for translating a design to Python - explain why the order of two statements cannot be swapped - write and test a translation of a supplied flowchart - choose test data that gives stronger evidence than a single run Inside: 9 explanation cells, 2 multiple-choice questions, 2 Python tasks, 2 fill-in-the-blanks cells and 2 written answers. 19 marks, about 45 minutes. Series: 1CP2-CT-1 · Programming foundations, part 6 of 7.
Worksheet1CP2-P-7.5 Protocols and responsibilities by layer
Part 5 · 1CP2-P-7 · Embedded systems, IoT and TCP/IP
The protocol worksheet, placing each named protocol at the layer it works in and the task it exists to do. Students will: - explain one advantage of HTTPS over HTTP for a submitted password - compare POP3 with IMAP for a user reading email on two devices - identify the layer Ethernet and Wi-Fi operate at - name the most suitable protocol for a stated task - explain why devices need agreed protocols to communicate at all Inside: 6 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-7 · Embedded systems, IoT and TCP/IP, part 5 of 6.
Worksheet1CP2-CT-7.5 Programming subprograms and libraries checkpoint
Part 5 · 1CP2-CT-7 · Subprograms, scope and libraries
The checkpoint for the whole programming topic 7 series, sampling constructs, subprograms, scope, maths methods and output formatting. Students will: - predict the output of a program that calls its own functions - trace a function call and record the values that change - define a local variable and justify limiting global ones - select the permitted method for a stated calculation - construct a program that separates calculation from presentation Inside: 4 explanation cells, 3 multiple-choice questions, 1 Python task, 1 trace table and 4 written answers. 17 marks, about 45 minutes. Series: 1CP2-CT-7 · Subprograms, scope and libraries, part 5 of 5.
Worksheet1CP2-P-6.5 Copper fibre and broadband
Part 5 · 1CP2-P-6 · Networks
The transmission media worksheet, comparing copper and fibre by the signal each one carries. Students will: - explain how data travels along copper and along fibre - compare the two media for a long high-capacity link - choose a medium for an environment with electrical interference - explain how a fibre final section improves a broadband connection - select a medium from the requirements of a scenario Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 5 of 8.
Worksheet1CP2-P-5.5 Robust software audit trails and code reviews
Part 5 · 1CP2-P-5 · Cyber security and robust software
The robust software worksheet, closing the loop from designing carefully to recording evidence and inspecting code. Students will: - recognise behaviour that is strong evidence of robustness - explain how a named weakness could be exploited and how to reduce it - use an audit trail as evidence, and state one of its limitations - compare human and automated code review - recommend improvements from the symptoms a system shows Inside: 8 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-5 · Cyber security and robust software, part 5 of 6.
Worksheet1CP2-CT-5.5 Writing and appending CSV files
Part 5 · 1CP2-CT-5 · Merge sort, files and authentication
The writing worksheet, and the difference between adding to a file and replacing it. Students will: - choose between write mode and append mode for a requirement - predict the file contents a program produces - create a comma-separated report from a structure - explain what writelines does and does not add - give a normal and a boundary test with expected file contents Inside: 7 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 3 written answers. 17 marks, about 45 minutes. Series: 1CP2-CT-5 · Merge sort, files and authentication, part 5 of 7.
Worksheet1CP2-P-4.5 Utility software file repair backup and compression
Part 5 · 1CP2-P-4 · Operating systems and utilities
The utility software worksheet, covering repair, backup strategy and compression as three different jobs. Students will: - describe what a file-repair utility does - explain why repair utilities do not remove the need for backups - state what a restore from full plus incremental backups requires - compare full and incremental backup for a large changing drive - recommend where compression helps and where it does not Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 19 marks, about 45 minutes. Series: 1CP2-P-4 · Operating systems and utilities, part 5 of 7.
Worksheet1CP2-CT-4.5 Linear search in one dimension
Part 5 · 1CP2-CT-4 · Structures, validation and search
The search worksheet, maintaining the three pieces of state a linear search needs and stopping correctly. Students will: - count the comparisons a search makes - trace a linear search to its termination - explain why both loop conditions are needed - write a complete search of their own - preserve a correct not-found outcome Inside: 6 explanation cells, 2 multiple-choice questions, 1 Python task, 1 trace table, 1 fill-in-the-blanks cell and 2 written answers. 14 marks, about 45 minutes. Series: 1CP2-CT-4 · Structures, validation and search, part 5 of 7.
Worksheet1CP2-P-3.5 Address buses and addressable memory
Part 5 · 1CP2-P-3 · Architecture and storage
The addressing worksheet, turning a bus width into a count of locations and then into a capacity. Students will: - calculate the locations an address bus of a given width can select - show the expression as well as the result - state what else is needed to convert locations into bytes - distinguish the effect of address-bus width from data-bus width - explain why one extra address bit doubles the locations Inside: 6 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-3 · Architecture and storage, part 5 of 7.
Worksheet1CP2-CT-3.5 Procedures and parameters
Part 5 · 1CP2-CT-3 · Lists, iteration and subprograms
The first subprogram worksheet, separating defining a procedure from calling it, then adding parameters. Students will: - tell the definition of a procedure apart from a call to it - predict the output order of a program that calls procedures - write a procedure that takes one parameter - pass two arguments in the correct order - explain how a procedure supports separation of concerns Inside: 7 explanation cells, 3 multiple-choice questions, 2 Python tasks, 1 fill-in-the-blanks cell and 2 written answers. 18 marks, about 45 minutes. Series: 1CP2-CT-3 · Lists, iteration and subprograms, part 5 of 7.
Worksheet1CP2-P-2.5 Hexadecimal and binary
Part 5 · 1CP2-P-2 · Signed data and encoding
The hexadecimal worksheet, built on the nibble mapping so conversion never becomes guesswork. Students will: - recall the mapping between a four-bit nibble and one hexadecimal digit - convert 8-bit binary to two hexadecimal digits - convert two hexadecimal digits to 8-bit binary - explain why programmers write long binary values in hexadecimal - correct a conversion presented at the wrong width Inside: 7 explanation cells, 2 multiple-choice questions, 3 number cells, 1 fill-in-the-blanks cell and 2 written answers. 19 marks, about 45 minutes. Series: 1CP2-P-2 · Signed data and encoding, part 5 of 7.
Worksheet1CP2-CT-2.5 Boolean operators and compound conditions
Part 5 · 1CP2-CT-2 · Selection, strings and while loops
The Boolean worksheet, teaching AND, OR and NOT as meanings first and syntax second. Students will: - state what AND, OR and NOT each require to be true - complete a truth table systematically - translate a requirement into a compound condition - write a program that acts on a compound condition - use NOT without accidentally reversing the whole rule Inside: 8 explanation cells, 2 multiple-choice questions, 2 Python tasks, 2 fill-in-the-blanks cells and 1 written answer. 19 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 5 of 8.
Worksheet1CP2-P-1.5 Binary foundations checkpoint
Part 5 · 1CP2-P-1 · Binary foundations
The checkpoint for the whole Binary foundations series, sampling every method the four worksheets taught. Students will: - calculate state counts and unsigned maximums correctly - convert in both directions at the full 8-bit width - add positive 8-bit integers and identify overflow - explain what overflow means for a stored reading - represent and interpret two's complement patterns Inside: 7 explanation cells, 3 multiple-choice questions, 7 number cells and 1 written answer. 18 marks, about 45 minutes. Series: 1CP2-P-1 · Binary foundations, part 5 of 5.
Worksheet1CP2-CT-1.5 Flowchart symbols and sequence
Part 5 · 1CP2-CT-1 · Programming foundations
The flowchart worksheet, giving students a shared notation for designs before they translate them. Students will: - name the six standard flowchart symbols and what each is for - follow a flowchart in the order its flow arrows set - supply a missing process step in a partly drawn design - diagnose a flowchart whose steps are in the wrong order - specify a complete sequence flowchart precisely Inside: 9 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 2 written answers. 18 marks, about 45 minutes. Series: 1CP2-CT-1 · Programming foundations, part 5 of 7.
Worksheet1CP2-P-7.4 The four-layer TCP IP model
Part 4 · 1CP2-P-7 · Embedded systems, IoT and TCP/IP
The TCP/IP worksheet, establishing the four layers in order and the direction data moves through them. Students will: - place the four layers in order and state the direction of travel - assign the right responsibility to each layer - describe two responsibilities of the transport layer - explain one benefit of a layered protocol model - follow a web request down the stack and back up at the receiver Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-7 · Embedded systems, IoT and TCP/IP, part 4 of 6.
Worksheet1CP2-CT-7.4 Structured programming problem solving
Part 4 · 1CP2-CT-7 · Subprograms, scope and libraries
The structured problem-solving worksheet, working from a stated requirement to a tested program built from cohesive functions. Students will: - state the inputs, processes and outputs a requirement implies - trace a function call to check it returns what the caller needs - explain a boundary result produced by selection inside a function - choose a boundary test and say what it checks - identify and correct a runtime failure on an empty list Inside: 7 explanation cells, 2 multiple-choice questions, 1 Python task, 1 trace table and 4 written answers. 17 marks, about 45 minutes. Series: 1CP2-CT-7 · Subprograms, scope and libraries, part 4 of 5.
Worksheet1CP2-P-6.4 Transmission units and calculations
Part 4 · 1CP2-P-6 · Networks
The calculation worksheet, making units compatible before any transmission time is worked out. Students will: - convert between bytes and bits correctly - calculate a transmission time from a size and a rate - construct an expression for a mixed-unit problem - match time units as well as data units - explain why using binary multipliers for a bit rate gives a wrong answer Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 4 of 8.
Worksheet1CP2-P-5.4 Protecting systems and data
Part 4 · 1CP2-P-5 · Cyber security and robust software
The protection worksheet, layering encryption, policy, backup and anti-malware by the purpose each one serves. Students will: - explain what encryption protects and state one limitation - give suitable acceptable use provisions and say how one reduces risk - state what restoring from full plus incremental backups requires - explain why RAID is not a backup - recommend a layered set of controls for a stated scenario Inside: 7 explanation cells, 5 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-5 · Cyber security and robust software, part 4 of 6.
Worksheet1CP2-CT-5.4 Processing CSV records
Part 4 · 1CP2-CT-5 · Merge sort, files and authentication
The record processing worksheet, splitting a line into fields and converting the ones that must be numbers. Students will: - split a record and read the field they need - explain the error that removing a conversion would cause - trace a loop that totals a numeric field across records - process several records into a new structure - describe checks that protect a program's assumptions about a file Inside: 6 explanation cells, 3 multiple-choice questions, 1 Python task, 1 trace table, 1 fill-in-the-blanks cell and 2 written answers. 15 marks, about 45 minutes. Series: 1CP2-CT-5 · Merge sort, files and authentication, part 4 of 7.
Worksheet1CP2-P-4.4 User management permissions and interfaces
Part 4 · 1CP2-P-4 · Operating systems and utilities
The user management worksheet, separating who someone is from what they are allowed to do, then comparing interfaces. Students will: - apply read-only permissions to a stated action - explain why users receive only the permissions their work needs - compare a graphical interface with a command line for a given user - describe user-management actions for a temporary account - separate authentication from permissions correctly Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 16 marks, about 45 minutes. Series: 1CP2-P-4 · Operating systems and utilities, part 4 of 7.
Worksheet1CP2-CT-4.4 Validating user input
Part 4 · 1CP2-CT-4 · Structures, validation and search
The validation worksheet, covering the four standard checks and the loop that applies them until the input is acceptable. Students will: - match a rule to the validation check that tests it - explain why a value is validated before it is used in a calculation - apply a format or pattern check - write the Boolean condition that is true when input is invalid - distinguish validation from verification and authentication Inside: 7 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 2 written answers. 16 marks, about 45 minutes. Series: 1CP2-CT-4 · Structures, validation and search, part 4 of 7.
Worksheet1CP2-P-3.4 RAM volatility and clock speed
Part 4 · 1CP2-P-3 · Architecture and storage
The memory and performance worksheet, separating volatility from purpose and clock speed from capacity. Students will: - say where a running program's instructions are held - explain what happens to active data when power is removed - compare RAM with secondary storage by purpose and volatility - explain how clock speed affects the performance of a comparable CPU - correct a claim that confuses units and volatility Inside: 6 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 19 marks, about 45 minutes. Series: 1CP2-P-3 · Architecture and storage, part 4 of 7.
Worksheet1CP2-CT-3.4 Iterating through a list
Part 4 · 1CP2-CT-3 · Lists, iteration and subprograms
The list iteration worksheet, visiting items one at a time and tracing the state that changes as the loop runs. Students will: - say how many times a loop over a list repeats - complete a trace table for a loop that accumulates a value - explain why accumulated outputs differ from the raw items - process only the items that meet a condition - compare iterating by item with iterating by index Inside: 6 explanation cells, 2 multiple-choice questions, 1 Python task, 1 trace table, 1 fill-in-the-blanks cell and 2 written answers. 14 marks, about 45 minutes. Series: 1CP2-CT-3 · Lists, iteration and subprograms, part 4 of 7.
Worksheet1CP2-P-2.4 Binary shift applications and limitations
Part 4 · 1CP2-P-2 · Signed data and encoding
The applications worksheet, giving students a five-step method for choosing and defending a shift. Students will: - follow a five-step method from requirement to justified answer - identify the direction and number of places from a pair of patterns - apply a shift to an unsigned value and state the stored result - choose a shift that divides a signed value while preserving its meaning - state the question that must be answered before choosing a shift type Inside: 7 explanation cells, 2 multiple-choice questions, 1 number cell, 1 fill-in-the-blanks cell and 3 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-2 · Signed data and encoding, part 4 of 7.
Worksheet1CP2-CT-2.4 Multi-branch selection and readable code
Part 4 · 1CP2-CT-2 · Selection, strings and while loops
The multi-branch worksheet, where the order of the conditions becomes the thing that decides whether a program is right. Students will: - order thresholds in an if-elif-else chain correctly - explain the logic error a wrongly ordered chain produces - say what happens after one condition in a chain is true - choose between a chain and nested selection - improve the readability of a working but unclear program Inside: 7 explanation cells, 3 multiple-choice questions, 2 Python tasks, 1 fill-in-the-blanks cell and 2 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 4 of 8.
Worksheet1CP2-P-1.4 Signed integers and two's complement foundations
Part 4 · 1CP2-P-1 · Binary foundations
The signed representation worksheet, introducing two's complement as the method behind the negative patterns. Students will: - decide whether a value needs a signed or an unsigned representation - state the 8-bit ranges for both interpretations - interpret an 8-bit two's complement pattern in denary - represent a negative denary value using the full invert-and-add method - diagnose the recurring error of stopping after the inversion Inside: 9 explanation cells, 1 multiple-choice question, 4 number cells, 3 fill-in-the-blanks cells and 1 written answer. 20 marks, about 45 minutes. Series: 1CP2-P-1 · Binary foundations, part 4 of 5.
Worksheet1CP2-CT-1.4 Data types, input, conversion and debugging
Part 4 · 1CP2-CT-1 · Programming foundations
The data types worksheet, covering why keyboard input arrives as text and what has to happen next. Students will: - choose the appropriate primitive type for a given value - convert input to a number before calculating with it - build a complete input, processing and output program - read a runtime error and say what caused it - work through one full debugging cycle and state the amendment Inside: 9 explanation cells, 3 multiple-choice questions, 2 Python tasks, 3 fill-in-the-blanks cells and 1 written answer. 20 marks, about 45 minutes. Series: 1CP2-CT-1 · Programming foundations, part 4 of 7.
Worksheet1CP2-P-7.3 Packet switching and packet structure
Part 3 · 1CP2-P-7 · Embedded systems, IoT and TCP/IP
The packet worksheet, reading the structure of a single packet and then following many of them across a network. Students will: - identify the header fields that decide where a packet goes - describe how a file is transmitted by packet switching - explain why packets from one message can arrive out of order - explain how a checksum is used and what happens when it fails - explain how the receiver reconstructs the original data Inside: 5 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-7 · Embedded systems, IoT and TCP/IP, part 3 of 6.
Worksheet1CP2-CT-7.3 Maths time and formatted output
Part 3 · 1CP2-CT-7 · Subprograms, scope and libraries
The maths and formatting worksheet, using only the methods the Pearson subset permits and displaying the result deliberately. Students will: - match each permitted maths method to what it actually does - explain why rounding and format strings can give different output - describe the effect of pausing a program with a timed delay - choose the correct method when a division must round upwards - format a number to a fixed width and a fixed number of decimal places Inside: 7 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 2 written answers. 16 marks, about 45 minutes. Series: 1CP2-CT-7 · Subprograms, scope and libraries, part 3 of 5.
Worksheet1CP2-P-6.3 Network performance bandwidth latency and range
Part 3 · 1CP2-P-6 · Networks
The performance worksheet, keeping bandwidth, latency and range as three separate properties with three separate units. Students will: - choose the appropriate unit for each property - explain how low bandwidth affects several simultaneous streams - explain why latency matters even when bandwidth is sufficient - identify the property a scenario actually constrains - correct a claim that confuses range with bandwidth Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 3 of 8.
Worksheet1CP2-P-5.3 Social engineering attacks
Part 3 · 1CP2-P-5 · Cyber security and robust software
The social engineering worksheet, covering the four required techniques and the point at which each manipulation chain can be broken. Students will: - identify the dominant technique in a described attack - explain how a phishing attempt leads to unauthorised access - identify warning signs in a pretexting call - describe safe actions that break the manipulation chain - compare social engineering with exploiting a technical vulnerability Inside: 5 explanation cells, 5 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-5 · Cyber security and robust software, part 3 of 6.
Worksheet1CP2-CT-5.3 Reading CSV text files
Part 3 · 1CP2-CT-5 · Merge sort, files and authentication
The file reading worksheet, following connect, read and close on a real comma-separated file. Students will: - open a file in read mode and close it deliberately - predict what successive read calls return - explain why a further read past the end returns an empty string - read every line of a file in a loop - compare readline, readlines and a for loop over the file Inside: 7 explanation cells, 3 multiple-choice questions, 2 Python tasks, 1 fill-in-the-blanks cell and 2 written answers. 15 marks, about 45 minutes. Series: 1CP2-CT-5 · Merge sort, files and authentication, part 3 of 7.
Worksheet1CP2-P-4.3 Peripheral management drivers and interrupts
Part 3 · 1CP2-P-4 · Operating systems and utilities
The peripheral worksheet, covering the driver that translates requests and the interrupt that asks for attention. Students will: - explain why a device needs a driver - describe how an interrupt lets the OS respond to a device condition - follow one complete request from application to device - state a benefit of keeping device-specific code in drivers - correct a confusion between a driver and a hardware signal Inside: 4 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 15 marks, about 45 minutes. Series: 1CP2-P-4 · Operating systems and utilities, part 3 of 7.
Worksheet1CP2-CT-4.3 Traversing two-dimensional lists
Part 3 · 1CP2-CT-4 · Structures, validation and search
The traversal worksheet, where the outer loop chooses the row and the inner loop chooses the field. Students will: - calculate how many times an inner-loop body executes - trace a nested traversal that accumulates a total - process one field from every record - choose the smallest traversal a requirement actually needs - explain the effect of resetting a total inside the row loop Inside: 6 explanation cells, 2 multiple-choice questions, 1 Python task, 1 trace table, 1 fill-in-the-blanks cell and 2 written answers. 14 marks, about 45 minutes. Series: 1CP2-CT-4 · Structures, validation and search, part 3 of 7.
Worksheet1CP2-P-3.3 The fetch decode execute cycle
Part 3 · 1CP2-P-3 · Architecture and storage
The cycle worksheet, taken one stage at a time and then described end to end. Students will: - name the three recurring stages and state what each produces - model the fetch stage using the registers and buses involved - distinguish execution from decoding - describe the whole cycle from locating an instruction to carrying it out - explain why the cycle repeats while a program runs Inside: 6 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-3 · Architecture and storage, part 3 of 7.
Worksheet1CP2-CT-3.3 For loops and range
Part 3 · 1CP2-CT-3 · Lists, iteration and subprograms
The count-controlled loop worksheet, reading range() precisely before writing loops with it. Students will: - read the start, stop and step of a range correctly - predict the exact output of a for loop - explain why the stop value is not generated - construct a loop that repeats an exact number of times - use a loop to repeat processing, not only output Inside: 7 explanation cells, 2 multiple-choice questions, 2 Python tasks, 2 fill-in-the-blanks cells and 2 written answers. 19 marks, about 45 minutes. Series: 1CP2-CT-3 · Lists, iteration and subprograms, part 3 of 7.
Worksheet1CP2-P-2.3 Arithmetic binary shifts
Part 3 · 1CP2-P-2 · Signed data and encoding
The arithmetic shift worksheet, and the reason a signed value needs a different operation from an unsigned one. Students will: - apply an arithmetic right shift that preserves the sign bit - compare logical and arithmetic right shifts on the same pattern - state the defining difference between the two - explain why arithmetic left shift is not a safe way to double a negative - justify the result of a shift in denary terms Inside: 6 explanation cells, 2 multiple-choice questions, 3 number cells, 1 fill-in-the-blanks cell and 2 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-2 · Signed data and encoding, part 3 of 7.
Worksheet1CP2-CT-2.3 Simple selection and relational operators
Part 3 · 1CP2-CT-2 · Selection, strings and while loops
The first selection worksheet, covering the six relational operators and the shape of a one-way and two-way decision. Students will: - use each of the six relational operators correctly - tell the code inside a decision apart from the code after it - write a condition that includes its boundary value - write one-way and two-way selection of their own - choose test data either side of a boundary Inside: 7 explanation cells, 3 multiple-choice questions, 2 Python tasks, 2 fill-in-the-blanks cells and 2 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 3 of 8.
Worksheet1CP2-P-1.3 Binary addition and overflow
Part 3 · 1CP2-P-1 · Binary foundations
The arithmetic worksheet, teaching column addition first and only then what happens when the answer will not fit. Students will: - apply the four column facts of binary addition - add pairs of positive 8-bit integers from right to left - tell a carry within the columns apart from overflow out of them - decide whether an 8-bit addition overflows - explain the consequence of overflow for a stored value Inside: 10 explanation cells, 2 multiple-choice questions, 3 number cells, 2 fill-in-the-blanks cells and 1 written answer. 18 marks, about 45 minutes. Series: 1CP2-P-1 · Binary foundations, part 3 of 5.
Worksheet1CP2-CT-1.3 First programs, variables and constants
Part 3 · 1CP2-CT-1 · Programming foundations
The first Python worksheet of the course, turning an informal algorithm into working code. Students will: - predict the exact output order of a short program - store values in named variables and read them back - choose between a variable and a constant, and name each conventionally - follow how a value changes as a program runs - write a short program of their own and explain an assignment statement Inside: 9 explanation cells, 2 multiple-choice questions, 3 Python tasks, 2 fill-in-the-blanks cells and 2 written answers. 18 marks, about 45 minutes. Series: 1CP2-CT-1 · Programming foundations, part 3 of 7.
Worksheet1CP2-P-7.2 Internet of Things power privacy and security
Part 2 · 1CP2-P-7 · Embedded systems, IoT and TCP/IP
The Internet of Things worksheet, keeping privacy and security as separate concerns once an embedded device is connected. Students will: - explain what connecting an embedded device adds to it - separate a privacy concern from a security concern in one scenario - recommend and justify security actions for a connected device - explain how reporting less often extends battery life, and its trade-off - weigh a benefit of a connected service against its risk Inside: 6 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-7 · Embedded systems, IoT and TCP/IP, part 2 of 6.
Worksheet1CP2-CT-7.2 Subprograms parameters return values and scope
Part 2 · 1CP2-CT-7 · Subprograms, scope and libraries
The subprogram worksheet, separating what a procedure does from what a function returns and keeping scope under control. Students will: - distinguish a procedure from a function that returns a value - follow arguments, parameters and return values through nested calls - explain why a local variable suits an intermediate calculation - explain why a program should minimise global variables - propose subprogram responsibilities that separate concerns Inside: 7 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 3 written answers. 18 marks, about 45 minutes. Series: 1CP2-CT-7 · Subprograms, scope and libraries, part 2 of 5.
Worksheet1CP2-P-6.2 How the internet connects networks
Part 2 · 1CP2-P-6 · Networks
The internet worksheet, following one request from a typed address to the server that answers it. Students will: - distinguish the web from the internet - explain why a packet needs a destination IP address - describe the role of a router between networks - explain why protocols are needed for devices to communicate - describe the journey of a request including DNS and routing Inside: 6 explanation cells, 5 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 2 of 8.
Worksheet1CP2-CT-6.2 Planning composing and debugging Turtle programs
Part 2 · 1CP2-CT-6 · Turtle problem solving
The planning and debugging worksheet for the Turtle topic, preparing students for the practical checkpoint that follows it. Students will: - control outline, fill and circle drawing - compose a scene in layers, in a deliberate drawing order - use parameters to build related objects from one subprogram - debug from the visible symptom back to the cause - plan a drawing before constructing it The checkpoint itself stays in the Workspace, where a teacher can inspect both the program and the picture it made. Inside: 7 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 6 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-6 · Turtle problem solving, part 2 of 2.
Worksheet1CP2-P-5.2 Attackers and technical vulnerabilities
Part 2 · 1CP2-P-5 · Cyber security and robust software
The vulnerability worksheet, building a linked chain from a technical weakness to the harm an attacker causes with it. Students will: - explain why unpatched software increases risk - describe how an unpatched vulnerability could disrupt school systems - compare updating software with updating anti-malware - recommend proportionate immediate controls for a published vulnerability - replace a vague cause with a strong causal explanation Inside: 5 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-5 · Cyber security and robust software, part 2 of 6.
Worksheet1CP2-CT-5.2 Merging sorted lists with while
Part 2 · 1CP2-CT-5 · Merge sort, files and authentication
The implementation worksheet, advancing one pointer at a time and dealing with whatever is left over. Students will: - advance the correct pointer after each comparison - trace a merge and record the growing output - construct a complete merge of two sorted lists - decide what merging equal values should produce - explain why two remainder loops are needed Inside: 6 explanation cells, 3 multiple-choice questions, 1 Python task, 1 trace table, 1 fill-in-the-blanks cell and 2 written answers. 15 marks, about 45 minutes. Series: 1CP2-CT-5 · Merge sort, files and authentication, part 2 of 7.
Worksheet1CP2-P-4.2 Process and memory management
Part 2 · 1CP2-P-4 · Operating systems and utilities
The scheduling and memory worksheet, explaining how one processor appears to run several programs at once. Students will: - explain why an unfinished process returns to the queue - describe how scheduling makes processes appear to progress together - state accurately what virtual memory does - explain why excessive paging reduces performance - keep the terms program, process and file distinct Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 16 marks, about 45 minutes. Series: 1CP2-P-4 · Operating systems and utilities, part 2 of 7.
Worksheet1CP2-CT-4.2 Two-dimensional lists and indexing
Part 2 · 1CP2-CT-4 · Structures, validation and search
The two-dimensional worksheet, selecting a row first and a field second. Students will: - read a value using a row index and a field index - predict the exact outputs of a listing that indexes a table - create, read and update a two-dimensional structure - state the greatest valid indexes for a given shape - explain what makes a structure a record Inside: 6 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 2 written answers. 14 marks, about 45 minutes. Series: 1CP2-CT-4 · Structures, validation and search, part 2 of 7.
Worksheet1CP2-P-3.2 CPU components registers and buses
Part 2 · 1CP2-P-3 · Architecture and storage
The component worksheet, mapping the CPU and the three buses onto the work each one does. Students will: - distinguish the control unit from the ALU - describe what registers hold while an instruction is processed - distinguish the address bus from the data bus during a read - match a transfer to the bus that carries it - describe one complete memory read using all three buses Inside: 5 explanation cells, 4 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-3 · Architecture and storage, part 2 of 7.
Worksheet1CP2-CT-3.2 Manipulating one-dimensional lists
Part 2 · 1CP2-CT-3 · Lists, iteration and subprograms
The list manipulation worksheet, teaching append, insert and delete alongside the index shifts they cause. Students will: - append, insert and delete items in a list - follow how the indexes move as each operation is applied - carry out a specified sequence of changes in code - choose the operation that matches a stated requirement - diagnose an insertion placed at the wrong index Inside: 6 explanation cells, 2 multiple-choice questions, 1 Python task, 2 fill-in-the-blanks cells and 2 written answers. 16 marks, about 45 minutes. Series: 1CP2-CT-3 · Lists, iteration and subprograms, part 2 of 7.
Worksheet1CP2-P-2.2 Logical binary shifts
Part 2 · 1CP2-P-2 · Signed data and encoding
The logical shift worksheet, moving bits first and interpreting the stored value second. Students will: - apply a logical shift left or right by a given number of places - say what fills the vacated positions - explain why a right shift can lose precision - explain when the multiply-by-two shortcut is reliable - choose a shift that meets a stated requirement Inside: 6 explanation cells, 2 multiple-choice questions, 3 number cells, 1 fill-in-the-blanks cell and 2 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-2 · Signed data and encoding, part 2 of 7.
Worksheet1CP2-CT-2.2 Substrings and string methods
Part 2 · 1CP2-CT-2 · Selection, strings and while loops
The substring worksheet, adding slicing and the common string methods to indexing. Students will: - slice from a start position up to, but not including, a stop position - explain why a method returns a new string rather than changing the original - build a short identifier from parts of an input - use a position search and handle the not-found result - combine methods to clean and reformat a value Inside: 7 explanation cells, 2 multiple-choice questions, 3 Python tasks, 2 fill-in-the-blanks cells and 1 written answer. 19 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 2 of 8.
Worksheet1CP2-P-1.2 Unsigned 8-bit binary and denary
Part 2 · 1CP2-P-1 · Binary foundations
The second Principles worksheet, attaching place values to the eight bits so students can convert accurately in both directions. Students will: - use the correct terminology for width, most significant bit and least significant bit - convert 8-bit binary to denary using place values - convert denary to 8-bit binary, padding to the full width - explain why the width is part of the answer, not decoration - check a conversion before accepting it Inside: 9 explanation cells, 1 multiple-choice question, 4 number cells, 2 fill-in-the-blanks cells and 1 written answer. 20 marks, about 45 minutes. Series: 1CP2-P-1 · Binary foundations, part 2 of 5.
Worksheet1CP2-CT-1.2 Decomposition and abstraction
Part 2 · 1CP2-CT-1 · Programming foundations
The second Computational thinking worksheet, teaching decomposition and abstraction as two techniques that work together. Students will: - break a problem into purposeful sub-problems and say why that helps - decide which details a model should keep and which it should leave out - relate the detail kept to the purpose the model serves - apply both techniques to an unfamiliar system - explain a design decision rather than merely describe it Inside: 11 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 19 marks, about 45 minutes. Series: 1CP2-CT-1 · Programming foundations, part 2 of 7.
Worksheet1CP2-P-7.1 Embedded systems and control
Part 1 · 1CP2-P-7 · Embedded systems, IoT and TCP/IP
The opening principles worksheet in the later progression, reading every embedded system as sensing, processing and acting. Students will: - identify an embedded system from how it is built and used - compare an embedded system with a general-purpose computer - describe how sensor readings lead to an actuator response - explain why low power consumption matters in a wearable device - state an input, an output and the processor's role in a described system Inside: 6 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 17 marks, about 45 minutes. Series: 1CP2-P-7 · Embedded systems, IoT and TCP/IP, part 1 of 6.
Worksheet1CP2-CT-7.1 Programming constructs reactivation
Part 1 · 1CP2-CT-7 · Subprograms, scope and libraries
The later-course reactivation worksheet, joining sequence, selection and iteration back into one working program. Students will: - read a program by the state it changes rather than by its keywords - predict the exact output of an accumulator and counter loop - choose between a for loop and a while loop from the problem - identify why a while loop fails to terminate and correct it - construct an integrated program that totals and counts in one pass Inside: 6 explanation cells, 3 multiple-choice questions, 1 Python task, 1 trace table, 1 fill-in-the-blanks cell and 2 written answers. 15 marks, about 45 minutes. Series: 1CP2-CT-7 · Subprograms, scope and libraries, part 1 of 5.
Worksheet1CP2-P-6.1 Why networks LANs and WANs
Part 1 · 1CP2-P-6 · Networks
The opening networks worksheet, establishing why organisations connect devices at all and how a LAN differs from a WAN. Students will: - give a network benefit rather than a description of equipment - explain two reasons a school connects its computers - explain one disadvantage of depending on a network - compare a LAN with a WAN using geography and ownership - recommend how LANs and a WAN could serve a multi-site organisation Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-6 · Networks, part 1 of 8.
Worksheet1CP2-CT-6.1 Reading Turtle movement and repeated shapes
Part 1 · 1CP2-CT-6 · Turtle problem solving
The reading and prediction worksheet for the Turtle topic, sitting after the first two practical Workspace lessons. Students will: - track the Turtle's position, direction and pen state rather than just the commands - predict where a short route ends and what it draws - position the Turtle deliberately before drawing - replace repeated commands with iteration - reuse a shape through a subprogram Every listing here is for reading and prediction. Students draw and run their own Turtle programs in the Workspace lessons this worksheet sits between. Inside: 7 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 19 marks, about 45 minutes. Series: 1CP2-CT-6 · Turtle problem solving, part 1 of 2.
Worksheet1CP2-P-5.1 Malware types and behaviours
Part 1 · 1CP2-P-5 · Cyber security and robust software
The opening cyber security worksheet, classifying malware by the mechanism it uses rather than by the harm it causes. Students will: - compare a virus with a worm by mechanism - identify the malware type a scenario describes - explain how a Trojan reaches a system and one harm it causes - explain why paying a ransomware demand is not a recovery plan - describe two different impacts malware could have on a school Inside: 6 explanation cells, 5 multiple-choice questions, 1 fill-in-the-blanks cell and 6 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-5 · Cyber security and robust software, part 1 of 6.
Worksheet1CP2-CT-5.1 How merge sort works
Part 1 · 1CP2-CT-5 · Merge sort, files and authentication
The opening merge sort worksheet, following the divide and merge stages by hand before any code is written. Students will: - describe the divide stage and the merge stage separately - show the output after each comparison of a complete merge - explain why a merge only compares the two first unused values - identify the mistake behind a merge that concatenates instead - state one memory cost and one benefit of merge sort Inside: 6 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 17 marks, about 45 minutes. Series: 1CP2-CT-5 · Merge sort, files and authentication, part 1 of 7.
Worksheet1CP2-P-4.1 Operating systems and file management
Part 1 · 1CP2-P-4 · Operating systems and utilities
The opening systems software worksheet, naming the operating system's responsibilities and then working through file management in detail. Students will: - describe the purpose of an operating system accurately - explain how files are organised, stored and retrieved - calculate blocks and allocated space for a given file size - tell file management apart from process management - correct the claim that an application decides where a file is stored Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 15 marks, about 45 minutes. Series: 1CP2-P-4 · Operating systems and utilities, part 1 of 7.
Worksheet1CP2-CT-4.1 Formatting output with format
Part 1 · 1CP2-CT-4 · Structures, validation and search
The formatting worksheet, separating the value a program holds from the way it is presented. Students will: - read a format descriptor for width, alignment and decimal places - supply values in placeholder order - explain why fixed width suits a column of prices - construct a readable result row - diagnose a formatting failure caused by the wrong type Inside: 6 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 2 written answers. 14 marks, about 45 minutes. Series: 1CP2-CT-4 · Structures, validation and search, part 1 of 7.
Worksheet1CP2-P-3.1 The stored-program concept
Part 1 · 1CP2-P-3 · Architecture and storage
The opening architecture worksheet, establishing what the stored-program concept actually claims before any component is named. Students will: - define the stored-program concept accurately - follow a program from a stored file to a running process - state one benefit over a machine wired for one fixed task - distinguish the role of main memory from that of storage - correct the common claim that a program stays in RAM forever Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 3 written answers. 16 marks, about 45 minutes. Series: 1CP2-P-3 · Architecture and storage, part 1 of 7.
Worksheet1CP2-CT-3.1 One-dimensional lists and indexing
Part 1 · 1CP2-CT-3 · Lists, iteration and subprograms
The opening list worksheet, establishing indexing and length before anything is changed or looped over. Students will: - use the terms array, list and index correctly - read a value from a list by its index - predict the exact outputs of a short listing - create a list and use it in a program of their own - explain the runtime error an out-of-range index produces Inside: 6 explanation cells, 3 multiple-choice questions, 1 Python task, 1 fill-in-the-blanks cell and 2 written answers. 15 marks, about 45 minutes. Series: 1CP2-CT-3 · Lists, iteration and subprograms, part 1 of 7.
Worksheet1CP2-P-2.1 Two's complement conversion and range
Part 1 · 1CP2-P-2 · Signed data and encoding
The opening worksheet of the signed data series, converting two's complement in both directions and deriving the range it can hold. Students will: - interpret an 8-bit two's complement pattern using signed place values - explain why 10000000 represents minus 128 - represent a negative denary value at the full 8-bit width - derive the signed range from the width - explain why a value outside that range cannot be stored Inside: 6 explanation cells, 2 multiple-choice questions, 4 number cells, 1 fill-in-the-blanks cell and 2 written answers. 20 marks, about 45 minutes. Series: 1CP2-P-2 · Signed data and encoding, part 1 of 7.
Worksheet1CP2-CT-2.1 String length, position and indexing
Part 1 · 1CP2-CT-2 · Selection, strings and while loops
The opening string worksheet, establishing that positions begin at zero before anything is sliced. Students will: - use len() and read a character by its index - predict the exact output of a short indexing listing - explain what a negative index selects - complete and then write a lookup that indexes user input - debug an off-by-one index rather than blaming the data Inside: 7 explanation cells, 3 multiple-choice questions, 2 Python tasks, 1 fill-in-the-blanks cell and 2 written answers. 18 marks, about 45 minutes. Series: 1CP2-CT-2 · Selection, strings and while loops, part 1 of 8.
Worksheet1CP2-P-1.1 Binary patterns, bits and states
Part 1 · 1CP2-P-1 · Binary foundations
The opening Principles worksheet, building the idea of binary representation from the beginning, before any conversion or arithmetic. Students will: - define binary and bit, and say why two states are reliable to build with - explain why a pattern means nothing without a context - calculate how many patterns a given number of bits can make - distinguish the number of states from the largest unsigned value - repair the common error of confusing the two Inside: 9 explanation cells, 2 multiple-choice questions, 1 number cell, 2 fill-in-the-blanks cells and 2 written answers. 18 marks, about 45 minutes. Series: 1CP2-P-1 · Binary foundations, part 1 of 5.
Worksheet1CP2-CT-1.1 Problems, algorithms, sequence and IPO
Part 1 · 1CP2-CT-1 · Programming foundations
The opening Computational thinking worksheet, establishing what an algorithm is before any Python is written. Students will: - tell an algorithm apart from a restatement of the problem - say what makes a set of steps followable by someone else - put steps into a sequence that can actually be carried out - label the input, processing and output stages of a task - write and then improve a short informal algorithm Inside: 9 explanation cells, 2 multiple-choice questions, 4 fill-in-the-blanks cells and 2 written answers. 20 marks, about 45 minutes. Series: 1CP2-CT-1 · Programming foundations, part 1 of 7.
WorksheetJ277 2.1.2 Trace tables: iteration and nesting
Part 3 · J277 2.1.2 · Tracing and refining algorithms
Trace tables for loops and nested constructs, the Block A checkpoint. Students will: - trace a loop across repeated rows - keep the loop variable, condition, accumulator and output separate - finish the inner steps before moving to the next outer value - trace nested constructs without losing your place - check a traced answer against the program output Inside: 3 explanation cells, 3 trace tables, 2 multiple-choice questions and 3 written answers. 12 author-set marks plus the trace-table rows, about 45 minutes. Series: J277 2.1.2 · Tracing and refining algorithms, part 3 of 3.
WorksheetJ277 2.1.2 Trace tables: sequence and selection
Part 2 · J277 2.1.2 · Tracing and refining algorithms
Trace tables for sequence and selection, marked automatically row by row. Students will: - record variable and output changes in execution order - decide when a trace-table box should be left empty - trace a program containing a decision - use a completed trace to explain what a program produces - apply the method to an exam-style question Inside: 3 explanation cells, 3 trace tables, 2 multiple-choice questions and 2 written answers. 6 author-set marks plus the trace-table rows, about 45 minutes. Series: J277 2.1.2 · Tracing and refining algorithms, part 2 of 3.
WorksheetJ277 2.1.2 Completing, correcting and refining algorithms
Part 1 · J277 2.1.2 · Tracing and refining algorithms
The OCR question types that hand students an algorithm to complete, correct or refine. Students will: - work from the stated purpose and test data rather than guessing - complete missing statements in an algorithm - find and correct a logic error in an accumulator - validate an inclusive range correctly - refine an algorithm to meet a new requirement Inside: 7 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 23 marks, about 60 minutes. Series: J277 2.1.2 · Tracing and refining algorithms, part 1 of 3.
WorksheetJ277 1.5 Systems software consolidation
Part 3 · J277 1.5 · Systems software
The end-of-topic checkpoint for section 1.5, built around a community-library scenario. Students will: - select the correct operating system function for an unfamiliar scenario - explain memory, peripheral, user and file management without support - justify a utility choice for a stated organisation - replace circular definitions with a real task and its result - write a developed answer under exam conditions Inside: 3 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 6 written answers. 56 marks, about 75 minutes. Series: J277 1.5 · Systems software, part 3 of 3.
WorksheetJ277 1.5.2 Utility software
Part 2 · J277 1.5 · Systems software
The three utilities named in section 1.5, with the misconceptions about storage space and solid-state drives dealt with directly. Students will: - explain the overall purpose of utility software - explain encryption software and why it is required - explain fragmentation, defragmentation and the effect on a magnetic hard disk - explain data compression software and why it is required - select and justify a utility for a scenario Inside: 7 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 5 written answers. 50 marks, about 75 minutes. Series: J277 1.5 · Systems software, part 2 of 3.
WorksheetJ277 1.5.1 Operating systems
Part 1 · J277 1.5 · Systems software
The five operating system functions in OCR J277 section 1.5, each described by a real task and its result. Students will: - explain the overall purpose of an operating system - explain memory management and how it supports multitasking - explain peripheral management and the role of device drivers - explain user management and file management - describe user interface features and pick the right function for a scenario Inside: 7 explanation cells, 2 multiple-choice questions, 3 fill-in-the-blanks cells and 5 written answers. 56 marks, about 75 minutes. Series: J277 1.5 · Systems software, part 1 of 3.
WorksheetJ277 1.1 Systems architecture consolidation
Part 6 · J277 1.1 · Systems architecture
The end-of-topic checkpoint for OCR J277 section 1.1, mixing recall with an applied scenario and an extended answer. Students will: - recall CPU purpose, components and performance factors without support - apply Von Neumann architecture and the four required registers - explain the fetch-execute cycle in an unfamiliar context - choose a processor for a scenario and justify the choice - write an extended answer that develops several linked points Inside: 4 explanation cells, 1 multiple-choice question, 2 fill-in-the-blanks cells and 8 written answers. 61 marks, about 75 minutes. Series: J277 1.1 · Systems architecture, part 6 of 6.
WorksheetJ277 1.1.3 Embedded systems
Part 5 · J277 1.1 · Systems architecture
Embedded systems, the part of section 1.1 where marks are won by application rather than by naming a device. Students will: - define an embedded system - describe the characteristics typical of one - distinguish embedded from general-purpose systems - identify valid examples across a range of contexts - explain why a particular embedded system suits its task Inside: 6 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 39 marks, about 75 minutes. Series: J277 1.1 · Systems architecture, part 5 of 6.
WorksheetJ277 1.1.1 Fetch-execute cycle
Part 4 · J277 1.1 · Systems architecture
How the CPU actually runs a program, taught as the repeating cycle OCR describes as fetch, decode and execute. Students will: - describe what happens at each stage of the cycle - explain how the components and registers support each stage - distinguish an instruction from the data it uses - apply the cycle to an unfamiliar instruction - correct the misconceptions examiners see most often Inside: 6 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 37 marks, about 60 minutes. Series: J277 1.1 · Systems architecture, part 4 of 6.
WorksheetJ277 1.1.1 Von Neumann architecture and registers
Part 3 · J277 1.1 · Systems architecture
The stored-program model behind section 1.1, and the four registers OCR names by abbreviation. Students will: - distinguish an address from the contents stored at it - state what the PC, MAR, MDR and accumulator each hold - read a processing snapshot and say what happens next - describe the Von Neumann model of stored programs and data - apply the registers to processing scenarios Inside: 6 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 5 written answers. 43 marks, about 75 minutes. Series: J277 1.1 · Systems architecture, part 3 of 6.
WorksheetJ277 1.1.2 CPU performance
Part 2 · J277 1.1 · Systems architecture
The three characteristics OCR J277 uses to explain CPU performance: clock speed, cache size and number of cores. Students will: - explain clock speed, cache size and number of cores - build a cause-and-effect chain for each characteristic - compare processor specifications - justify a processor choice from several pieces of evidence - explain why more of one characteristic is not always a proportional gain Inside: 6 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 39 marks, about 75 minutes. Series: J277 1.1 · Systems architecture, part 2 of 6.
WorksheetJ277 1.1.1 Introducing the CPU
Part 1 · J277 1.1 · Systems architecture
The opening worksheet of OCR J277 section 1.1, introducing what the CPU is for and the components inside it. Students will: - state what a CPU does and why a computer needs one - identify the control unit, arithmetic logic unit, cache and registers - describe the job each component performs - recognise the fetch, decode and execute stages - apply component knowledge to familiar devices Inside: 6 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 29 marks, about 60 minutes. Series: J277 1.1 · Systems architecture, part 1 of 6.
WorksheetJ277 2.2.3 Procedures, scope and passing arrays
Part 5 · J277 2.2.3 · Strings, arrays and functions
Procedures, local and global scope, and passing arrays into and out of subprograms. Students will: - distinguish a procedure from a function - explain local and global scope - pass a list into a subprogram - return an updated array from a subprogram - choose between a procedure and a function for a task Inside: 5 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 21 marks, about 60 minutes. Series: J277 2.2.3 · Strings, arrays and functions, part 5 of 5.
WorksheetJ277 2.2.3 Functions, parameters and return values
Part 4 · J277 2.2.3 · Strings, arrays and functions
Functions, parameters and return values, and why parameters make one function reusable. Students will: - define a function with parameters and call it with arguments - return a value and store the result - distinguish a parameter from an argument - return a Boolean result from a test - explain why parameters make a function reusable Inside: 5 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 18 marks, about 45 minutes. Series: J277 2.2.3 · Strings, arrays and functions, part 4 of 5.
WorksheetJ277 2.2.3 Processing arrays with loops
Part 3 · J277 2.2.3 · Strings, arrays and functions
The loop patterns that appear in almost every OCR array question. Students will: - total and average the values in a list - count values that meet a condition - find a maximum or minimum correctly - update every element with a loop - debug a faulty minimum-finding algorithm Inside: 6 explanation cells, 4 runnable Python tasks, 3 multiple-choice questions and 2 written answers. 18 marks, about 45 minutes. Series: J277 2.2.3 · Strings, arrays and functions, part 3 of 5.
WorksheetJ277 2.2.3 One-dimensional arrays and Python lists
Part 2 · J277 2.2.3 · Strings, arrays and functions
One-dimensional arrays, represented in these worksheets by Python lists. Students will: - create a list and access elements by index - update an element in place - explain how an OCR array relates to a Python list - avoid index errors at the start and end of a list - build a list from a stated requirement Inside: 5 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 16 marks, about 45 minutes. Series: J277 2.2.3 · Strings, arrays and functions, part 2 of 5.
WorksheetJ277 2.2.3 String manipulation
Part 1 · J277 2.2.3 · Strings, arrays and functions
String handling in Python, indexed from zero, with slices that stop before their end position. Students will: - index a string and extract a single character - take a slice and explain where it stops - join strings with concatenation - change case and find a string's length - build a formatted result from several strings Inside: 5 explanation cells, 3 runnable Python tasks, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 17 marks, about 45 minutes. Series: J277 2.2.3 · Strings, arrays and functions, part 1 of 5.
WorksheetJ277 2.1 Algorithms consolidation
Part 4 · J277 2.1.3 · Searching and sorting
The Block B checkpoint, combining strings, arrays, subprograms, searching and sorting. Students will: - select a searching or sorting algorithm to suit the data - combine strings, arrays and subprograms in one solution - read unfamiliar code and predict its output - debug a premature return - justify an algorithm choice in exam terms Inside: 5 explanation cells, 3 runnable Python tasks, 3 multiple-choice questions and 5 written answers. 28 marks, about 60 minutes. Series: J277 2.1.3 · Searching and sorting, part 4 of 4.
WorksheetJ277 2.1.3 Merge sorting
Part 3 · J277 2.1.3 · Searching and sorting
Merge sort, split into the dividing step and the merging step OCR asks students to apply. Students will: - describe how a list is divided until each sublist holds one item - carry out the merge operation on two sorted sublists - apply merge sort to given data - recognise the algorithm from code - merge two sorted lists in Python Inside: 5 explanation cells, 2 runnable Python tasks, 3 multiple-choice questions and 2 written answers. 15 marks, about 45 minutes. Series: J277 2.1.3 · Searching and sorting, part 3 of 4.
WorksheetJ277 2.1.3 Bubble and insertion sorting
Part 2 · J277 2.1.3 · Searching and sorting
Bubble sort and insertion sort, traced by hand one pass at a time. Students will: - describe the steps of a bubble sort - describe the steps of an insertion sort - carry out one pass of each by hand - apply both algorithms to given data - recognise each algorithm from code Inside: 4 explanation cells, 2 runnable Python tasks, 4 multiple-choice questions and 4 written answers. 18 marks, about 60 minutes. Series: J277 2.1.3 · Searching and sorting, part 2 of 4.
WorksheetJ277 2.1.3 Linear and binary searching
Part 1 · J277 2.1.3 · Searching and sorting
The two search algorithms in OCR J277, understood and applied rather than memorised as code. Students will: - describe the steps of a linear search - describe the steps of a binary search - state the prerequisite binary search depends on - apply both algorithms to given data - recognise each algorithm from code Inside: 5 explanation cells, 2 runnable Python tasks, 3 multiple-choice questions and 3 written answers. 16 marks, about 45 minutes. Series: J277 2.1.3 · Searching and sorting, part 1 of 4.
WorksheetJ277 2.5 Programming languages and IDEs consolidation
Part 4 · J277 2.5 · Programming languages and IDEs
The consolidation worksheet for OCR J277 2.5, applied to a studio developing and releasing a Python game. Students will: - choose the language level a stated need calls for - select a translator and justify it against the studio's needs - read evidence from a development session and name the facility - structure an answer as point, mechanism and link - avoid generic lists in place of applied explanation Inside: 3 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 6 written answers. 38 marks, about 60 minutes. Series: J277 2.5 · Programming languages and IDEs, part 4 of 4.
WorksheetJ277 2.5.2 IDE tools and facilities
Part 3 · J277 2.5 · Programming languages and IDEs
The four IDE facilities OCR names, described by what they do for the programmer rather than by their own name. Students will: - explain what makes a development environment integrated - describe the editor and the features that help most - describe error diagnostics and the run-time environment - explain the translator's place in an IDE - avoid circular descriptions of a named tool Inside: 5 explanation cells, 1 runnable Python task, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 20 marks, about 45 minutes. Series: J277 2.5 · Programming languages and IDEs, part 3 of 4.
WorksheetJ277 2.5.1 Compilers and interpreters
Part 2 · J277 2.5 · Programming languages and IDEs
The two translators OCR requires, and the benefits and drawbacks that follow from how each one works. Students will: - explain why source code must be translated - describe how a compiler translates a program - describe how an interpreter translates a program - give the benefits and drawbacks of each - choose the translator that suits a stated situation Inside: 4 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 20 marks, about 45 minutes. Series: J277 2.5 · Programming languages and IDEs, part 2 of 4.
WorksheetJ277 2.5.1 High- and low-level languages
Part 1 · J277 2.5 · Programming languages and IDEs
What high-level and low-level actually describe, and why the difference matters to a programmer. Students will: - define high-level and low-level languages - explain what the terms do and do not describe - give the characteristics of each level - explain why a high-level program must be translated - choose a suitable level for a stated purpose Inside: 4 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 19 marks, about 45 minutes. Series: J277 2.5 · Programming languages and IDEs, part 1 of 4.
WorksheetJ277 2.2.1 Combining and nesting programming constructs
Part 7 · J277 2.2.1-2.2.2 · Programming fundamentals
Putting sequence, selection and iteration together, and reading the nesting that results. Students will: - combine the three constructs in one program - read nested code from the outside in - use indentation to control what belongs to each construct - count values that meet a condition inside a loop - find and fix indentation faults Inside: 6 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions and 2 written answers. 16 marks, about 45 minutes. Series: J277 2.2.1-2.2.2 · Programming fundamentals, part 7 of 7.
WorksheetJ277 2.2.1 Condition-controlled iteration
Part 6 · J277 2.2.1-2.2.2 · Programming fundamentals
Condition-controlled iteration, for when the number of repetitions is not known in advance. Students will: - explain when a while loop is the right choice - write a loop whose condition can become false - avoid loops that never finish - trace the values the condition depends on - repeat until a threshold is reached Inside: 6 explanation cells, 3 runnable Python tasks, 4 multiple-choice questions and 2 written answers. 15 marks, about 45 minutes. Series: J277 2.2.1-2.2.2 · Programming fundamentals, part 6 of 7.
WorksheetJ277 2.2.1 Count-controlled iteration
Part 5 · J277 2.2.1-2.2.2 · Programming fundamentals
Count-controlled iteration, used when the number of repetitions is known before the loop starts. Students will: - explain when a count-controlled loop is the right choice - use range() with one, two and three arguments - accumulate a running total inside a loop - predict how many times a loop body runs - generate a sequence from a stated requirement Inside: 7 explanation cells, 3 runnable Python tasks, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 16 marks, about 45 minutes. Series: J277 2.2.1-2.2.2 · Programming fundamentals, part 5 of 7.
WorksheetJ277 2.2.1 Selection
Part 4 · J277 2.2.1-2.2.2 · Programming fundamentals
Selection: choosing which statements run, and getting the boundaries right. Students will: - write an if statement with elif and else branches - use indentation to show which statements belong to a branch - handle boundary values correctly - choose between separate ifs and a chain of branches - write a program that sorts input into categories Inside: 5 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions and 2 written answers. 14 marks, about 45 minutes. Series: J277 2.2.1-2.2.2 · Programming fundamentals, part 4 of 7.
WorksheetJ277 2.2.1 Arithmetic, comparison and Boolean operators
Part 3 · J277 2.2.1-2.2.2 · Programming fundamentals
The arithmetic, comparison and Boolean operators OCR requires, in Python notation. Students will: - use arithmetic operators, including integer division and remainder - compare values with the correct comparison operator - combine conditions with and, or and not - distinguish assignment from comparison - translate a written requirement into a single condition Inside: 6 explanation cells, 3 runnable Python tasks, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 17 marks, about 45 minutes. Series: J277 2.2.1-2.2.2 · Programming fundamentals, part 3 of 7.
WorksheetJ277 2.2.2 Data types and casting
Part 2 · J277 2.2.1-2.2.2 · Programming fundamentals
The five data types OCR names, and converting between them when input arrives as text. Students will: - identify integer, real, Boolean, character and string data - choose a suitable data type for a scenario and justify it - explain why input arrives as a string - use int() and float() when numerical input is required - predict the result of an operation on mixed types Inside: 6 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 21 marks, about 60 minutes. Series: J277 2.2.1-2.2.2 · Programming fundamentals, part 2 of 7.
WorksheetJ277 2.2.1 Variables, constants, input and output
Part 1 · J277 2.2.1-2.2.2 · Programming fundamentals
The first programming worksheet: storing values, reading input and producing output. Students will: - assign values to variables and use them later - explain the difference between a variable and a constant - read input and produce readable output - use naming that communicates intent - write a short program from a stated requirement Inside: 5 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 15 marks, about 45 minutes. Series: J277 2.2.1-2.2.2 · Programming fundamentals, part 1 of 7.
WorksheetJ277 2.3 Producing robust programs consolidation
Part 7 · J277 2.3 · Producing robust programs
The consolidation worksheet for OCR J277 2.3, taking one festival booking system through validation, maintainability, testing and refinement. Students will: - implement a focused validation rule in Python - improve the maintainability of supplied code - find and refine a logic error - select test data for the stated rules - answer as feature, mechanism, then effect in this system Inside: 5 explanation cells, 2 runnable Python tasks, 1 multiple-choice question, 1 fill-in-the-blanks cell and 5 written answers. 34 marks, about 60 minutes. Series: J277 2.3 · Producing robust programs, part 7 of 7.
WorksheetJ277 2.3.2 Test data and test plans
Part 6 · J277 2.3 · Producing robust programs
Choosing test data deliberately, and setting it out in a test plan with expected results. Students will: - define normal, boundary, invalid and erroneous test data - choose values that sit on the edge of a stated rule - build a test plan with expected results - recognise when more than one label applies to a value - use an expected result to expose a fault Inside: 5 explanation cells, 1 runnable Python task, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 21 marks, about 45 minutes. Series: J277 2.3 · Producing robust programs, part 6 of 7.
WorksheetJ277 2.3.2 Testing programs and identifying errors
Part 5 · J277 2.3 · Producing robust programs
What testing is for, how it differs from validation, and how to identify and refine the two types of error. Students will: - state the purposes of testing a program - distinguish iterative testing from final testing - separate testing from validation - tell a syntax error from a logic error - refine a program once a fault has been found Inside: 6 explanation cells, 1 runnable Python task, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 17 marks, about 45 minutes. Series: J277 2.3 · Producing robust programs, part 5 of 7.
WorksheetJ277 2.3.1 Maintainable programs
Part 4 · J277 2.3 · Producing robust programs
The four maintainability techniques OCR requires, applied to code that already works but is hard to change. Students will: - explain what maintainability means and who it is for - use subprograms to break a program into focused parts - apply consistent naming conventions and indentation - comment code where a comment adds something - suggest only the improvements a given piece of code needs Inside: 5 explanation cells, 1 runnable Python task, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 20 marks, about 45 minutes. Series: J277 2.3 · Producing robust programs, part 4 of 7.
WorksheetJ277 2.3.1 Programming validation and authentication
Part 3 · J277 2.3 · Producing robust programs
Defensive design written as runnable Python, using a loop that keeps asking until the input is acceptable. Students will: - write the four parts of a reliable validation loop - express the invalid condition rather than the valid one - validate a number against a stated range - validate an entry against a list of accepted values - write a simple authentication check Inside: 8 explanation cells, 4 runnable Python tasks, 1 multiple-choice question and 2 written answers. 17 marks, about 45 minutes. Series: J277 2.3 · Producing robust programs, part 3 of 7.
WorksheetJ277 2.3.1 Input validation methods
Part 2 · J277 2.3 · Producing robust programs
The validation methods OCR expects, and how to apply one to the input a question actually describes. Students will: - name the common validation methods and what each checks - choose a suitable method for a stated input - explain a method against the scenario rather than in general - explain what validation does not prove - describe what a program should do with invalid data Inside: 5 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 22 marks, about 45 minutes. Series: J277 2.3 · Producing robust programs, part 2 of 7.
WorksheetJ277 2.3.1 Defensive design and authentication
Part 1 · J277 2.3 · Producing robust programs
The first robust programs worksheet for OCR J277 2.3.1, on anticipating misuse and confirming who a user is. Students will: - explain what defensive design means - anticipate accidental and deliberate misuse of a program - describe how authentication confirms a user's identity - separate authentication from input validation - write a simple authentication check in Python Inside: 5 explanation cells, 2 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 17 marks, about 45 minutes. Series: J277 2.3 · Producing robust programs, part 1 of 7.
WorksheetJ277 2 Paper 2 diagnostic and misconception clinic
Part 5 · J277 Paper 2 · Exam transition
Five clinics on the Paper 2 errors that repeatedly cost marks, each one diagnosed and then applied. Students will: - distinguish validation from test data - use elements, indexes, return and print correctly - write condition-controlled iteration that stops when it should - separate searching, Boolean logic and program errors - describe translators and IDE facilities precisely Inside: 7 explanation cells, 1 runnable Python task, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 22 marks, about 45 minutes. Series: J277 Paper 2 · Exam transition, part 5 of 5.
WorksheetJ277 2 Paper 2 independent Section B mini-assessment
Part 4 · J277 Paper 2 · Exam transition
A 30-mark independent Section B mini-assessment, matching the total OCR gives to Section B. Students will: - work from concise requirements, as in an examination - write a program that calculates league points - validate a score against stated rules - find the highest value in a set of scores - refine a program that does not yet meet its requirements Inside: 7 explanation cells, 4 runnable Python tasks and 3 written answers. 30 marks, about 60 minutes. Series: J277 Paper 2 · Exam transition, part 4 of 5.
WorksheetJ277 2 Paper 2 guided Section B programming scenario
Part 3 · J277 Paper 2 · Exam transition
A sustained Section B booking scenario taken through all four skills: design, write, test and refine. Students will: - design a solution before writing any code - write a calculation function to a stated specification - add range validation that rejects unsuitable input - process a one-dimensional array of bookings - test a program, then refine an incorrect version Inside: 8 explanation cells, 4 runnable Python tasks and 3 written answers. 33 marks, about 60 minutes. Series: J277 Paper 2 · Exam transition, part 3 of 5.
WorksheetJ277 2 Paper 2 Section A mixed practice
Part 2 · J277 Paper 2 · Exam transition
Mixed Section A practice across the Paper 2 specification, usable as a full set or as a shorter diagnostic. Students will: - recognise which topic an unlabelled question is testing - trace an algorithm and record each step in a trace table - apply accurate knowledge to an unfamiliar context - work at about one minute per available mark - decide which topics to revisit from the feedback Inside: 3 explanation cells, 1 trace table, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 6 written answers. 31 author-set marks plus the trace-table rows, about 60 minutes. Series: J277 Paper 2 · Exam transition, part 2 of 5.
WorksheetJ277 2 Paper 2 exam language and response precision
Part 1 · J277 Paper 2 · Exam transition
How OCR Paper 2 is structured, and what each question's wording asks you to produce. Students will: - describe what Section A and Section B each assess - decide the response form a question requires - turn a vague answer into one that earns the marks - write a programming response with the precision a marker needs - use a repeatable checking routine before moving on Inside: 6 explanation cells, 1 runnable Python task, 1 multiple-choice question, 1 fill-in-the-blanks cell and 3 written answers. 18 marks, about 45 minutes. Series: J277 Paper 2 · Exam transition, part 1 of 5.
WorksheetJ277 1 Paper 1 diagnostic and misconception clinic
Part 5 · J277 Paper 1 · Exam transition
Six clinics on the Paper 1 misunderstandings that most often stop partial knowledge becoming marks. Students will: - diagnose the mistaken idea behind a tempting wrong answer - restate the idea in precise specification language - apply the corrected idea in a new context - separate the pairs of terms that are most often confused - record which clinics need revisiting Inside: 8 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 7 written answers. 26 marks, about 60 minutes. Series: J277 Paper 1 · Exam transition, part 5 of 5.
WorksheetJ277 1 Paper 1 independent mini-assessment
Part 4 · J277 Paper 1 · Exam transition
A 40-mark independent mini-assessment sampling all six OCR J277 Paper 1 specification areas. Students will: - answer under independent, non-calculator conditions - show calculation and binary working in full - match the length of an answer to the marks available - move between systems, data, networks and impacts without prompts - use the feedback to target revision afterwards Inside: 7 explanation cells, 1 number grid, 4 multiple-choice questions and 10 written answers. 40 marks, about 60 minutes. Series: J277 Paper 1 · Exam transition, part 4 of 5.
WorksheetJ277 1 Paper 1 mixed knowledge and application
Part 3 · J277 Paper 1 · Exam transition
Mixed Paper 1 retrieval across one mobile science lab, with the topic no longer named for you. Students will: - decide which specification area a question is testing - apply hardware and memory knowledge to a described system - apply network, security and impact knowledge to the same context - work with less scaffolding as the worksheet progresses - make and justify an independent technical decision Inside: 7 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 8 written answers. 38 marks, about 60 minutes. Series: J277 Paper 1 · Exam transition, part 3 of 5.
WorksheetJ277 1 Paper 1 calculations and working
Part 2 · J277 Paper 1 · Exam transition
Non-calculator Paper 1 arithmetic, practised with the working set out the way a marker needs to see it. Students will: - convert between denary, binary and hexadecimal - add binary numbers and handle a carry - carry out left and right binary shifts - calculate image and sound file sizes with the correct units - check whether an answer is a sensible size Inside: 7 explanation cells, 3 number grids, 2 multiple-choice questions and 4 written answers. 36 marks, about 60 minutes. Series: J277 Paper 1 · Exam transition, part 2 of 5.
WorksheetJ277 1 Paper 1 exam language and response precision
Part 1 · J277 Paper 1 · Exam transition
The first Paper 1 exam transition worksheet, making the structure of a strong written answer visible. Students will: - read the command word and the marks together before answering - extend a technical point into how it works and what it means here - tell a definition apart from an explanation - justify a choice rather than list unsupported preferences - plan a balanced eight-mark extended response Inside: 7 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 5 written answers. 25 marks, about 45 minutes. Series: J277 Paper 1 · Exam transition, part 1 of 5.
WorksheetJ277 1.2.4 Binary shifts and consolidation
Part 5 · J277 1.2.4 · Number systems
Binary shifts, then a mixed checkpoint over the whole OCR number-systems topic. Students will: - carry out left and right binary shifts - connect the number of places with a power of two - identify direction and places from a before-and-after pair - explain when a fixed-width shift loses information - apply conversion, addition and overflow independently Inside: 5 explanation cells, 5 number grids, 3 multiple-choice questions and 3 written answers. 45 marks, about 75 minutes. Series: J277 1.2.4 · Number systems, part 5 of 5.
WorksheetJ277 1.2.4 Binary addition and overflow
Part 4 · J277 1.2.4 · Number systems
Adding binary numbers directly with the column method, and what happens when the answer will not fit. Students will: - recall the four binary addition facts - add two binary numbers using the column method - record carries clearly - explain what an overflow error is - recognise when an answer needs more than 8 bits Inside: 6 explanation cells, 3 number grids, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 27 marks, about 60 minutes. Series: J277 1.2.4 · Number systems, part 4 of 5.
WorksheetJ277 1.2.4 Hexadecimal conversion
Part 3 · J277 1.2.4 · Number systems
Hexadecimal, taught through the exact relationship between one hex digit and one group of four bits. Students will: - explain why hexadecimal is used alongside binary - recall the hexadecimal digits A to F - convert between 8-bit binary and two hexadecimal digits - convert between denary 0 to 255 and hexadecimal - complete a table holding all three representations Inside: 6 explanation cells, 5 number grids, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 35 marks, about 75 minutes. Series: J277 1.2.4 · Number systems, part 3 of 5.
WorksheetJ277 1.2.4 Binary and denary conversion
Part 2 · J277 1.2.4 · Number systems
Conversion in both directions, starting with visible place values and removing the prompts as the worksheet goes on. Students will: - convert an 8-bit binary number into denary - convert a denary whole number into 8-bit binary - include leading zeros when an 8-bit answer is required - check a conversion by reversing it - explain the method clearly Inside: 5 explanation cells, 4 number grids, 4 multiple-choice questions and 3 written answers. 25 marks, about 75 minutes. Series: J277 1.2.4 · Number systems, part 2 of 5.
WorksheetJ277 1.2.4 Binary foundations
Part 1 · J277 1.2.4 · Number systems
The starting point for binary in OCR J277 section 1.2, building place value before any conversion is attempted. Students will: - explain why computers represent data using binary - use the place values in an 8-bit binary number - identify the most significant and least significant bit - distinguish the number of values from the maximum value - explain why leading zeros do not change a value Inside: 6 explanation cells, 2 number grids, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 22 marks, about 60 minutes. Series: J277 1.2.4 · Number systems, part 1 of 5.
WorksheetJ277 1.3 Networks consolidation
Part 7 · J277 1.3 · Networks
The end-of-topic checkpoint for section 1.3, built around one school network scenario. Students will: - select the right network idea for an unfamiliar scenario - apply hardware, topology and performance knowledge to a school network - explain addressing, standards, protocols and layers without support - evaluate cloud services for a stated organisation - write a developed answer under exam conditions Inside: 3 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 8 written answers. 65 marks, about 75 minutes. Series: J277 1.3 · Networks, part 7 of 7.
WorksheetJ277 1.3.2 Protocols and layers
Part 6 · J277 1.3 · Networks
The protocols named in OCR J277 and the reason they are organised into layers. Students will: - explain the principle of a communication protocol - match TCP/IP, HTTP, HTTPS, FTP, SMTP, POP and IMAP to their purposes - describe the differences between closely related protocols - select protocols for a scenario - explain how protocols are layered and why that helps Inside: 6 explanation cells, 2 multiple-choice questions, 3 fill-in-the-blanks cells and 4 written answers. 42 marks, about 75 minutes. Series: J277 1.3 · Networks, part 6 of 7.
WorksheetJ277 1.3.2 Addressing and standards
Part 5 · J277 1.3 · Networks
Why a network needs two kinds of address, and why standards let equipment from different makers work together. Students will: - explain the different uses of IP and MAC addresses - recognise IPv4, IPv6 and MAC address formats - explain how routers and switches use different addresses - explain the principle and purpose of a computing standard - apply interoperability to a scenario involving several manufacturers Inside: 5 explanation cells, 2 multiple-choice questions, 4 fill-in-the-blanks cells and 5 written answers. 48 marks, about 75 minutes. Series: J277 1.3 · Networks, part 5 of 7.
WorksheetJ277 1.3.1 Internet, DNS, hosting and cloud
Part 4 · J277 1.3 · Networks
One request followed from a browser to an online resource, taking in DNS, hosting and cloud services. Students will: - describe the internet as a worldwide collection of networks - distinguish a web client from a web server - explain hosting - describe how DNS converts a domain name into an IP address - evaluate the advantages and disadvantages of cloud services Inside: 5 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 35 marks, about 60 minutes. Series: J277 1.3 · Networks, part 4 of 7.
WorksheetJ277 1.3 Network performance, connections and encryption
Part 3 · J277 1.3 · Networks
What makes a network fast, how devices connect, and why data in transit is encrypted. Students will: - explain the factors that affect network performance - compare wired Ethernet with wireless connections - distinguish Wi-Fi from Bluetooth by suitable use - recommend connection modes for a scenario - explain the principle of encryption Inside: 5 explanation cells, 4 multiple-choice questions, 3 fill-in-the-blanks cells and 3 written answers. 39 marks, about 75 minutes. Series: J277 1.3 · Networks, part 3 of 7.
WorksheetJ277 1.3.1 LAN hardware and topologies
Part 2 · J277 1.3 · Networks
Building a LAN from its components, then arranging the connections between them. Students will: - explain what a NIC, transmission medium, switch, wireless access point and router each do - distinguish the roles of a switch and a router - describe star, full mesh and partial mesh arrangements - compare the advantages and disadvantages of each topology - recommend hardware and a topology for a scenario Inside: 4 explanation cells, 5 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 33 marks, about 75 minutes. Series: J277 1.3 · Networks, part 2 of 7.
WorksheetJ277 1.3.1 Network types and roles
Part 1 · J277 1.3 · Networks
The opening worksheet of OCR J277 section 1.3, separating the area a network covers from the roles computers perform on it. Students will: - distinguish a LAN from a WAN - give common examples of both - describe the roles of clients, servers and peers - compare client-server with peer-to-peer - recommend a suitable arrangement for a scenario Inside: 5 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 6 written answers. 40 marks, about 75 minutes. Series: J277 1.3 · Networks, part 1 of 7.
WorksheetJ277 1.4 Network security consolidation
Part 3 · J277 1.4 · Network security
The consolidation worksheet for OCR J277 1.4, applying threats, vulnerabilities and prevention methods to a single event scenario. Students will: - identify how each specified attack is used and its purpose - select a suitable prevention method - explain how the method limits the named threat or vulnerability - recognise what a control cannot do - combine controls into a justified security plan Inside: 6 explanation cells, 3 multiple-choice questions, 2 fill-in-the-blanks cells and 7 written answers. 40 marks, about 60 minutes. Series: J277 1.4 · Network security, part 3 of 3.
WorksheetJ277 1.4.2 Preventing vulnerabilities
Part 2 · J277 1.4 · Network security
All seven prevention methods in section 1.4, each tied to the threat it limits and the limitation it carries. Students will: - explain penetration testing, anti-malware software and firewalls - explain user access levels and strong passwords - explain encryption and physical security - match each control to the threat it limits and name its limitation - recommend a layered set of controls for a scenario Inside: 7 explanation cells, 2 multiple-choice questions, 3 fill-in-the-blanks cells and 4 written answers. 52 marks, about 75 minutes. Series: J277 1.4 · Network security, part 2 of 3.
WorksheetJ277 1.4.1 Threats and attacks
Part 1 · J277 1.4 · Network security
The forms of attack named in OCR J277 section 1.4, studied defensively: no attack code and no technical commands. Students will: - explain malware and the behaviour of its common types - explain social engineering and phishing - explain brute-force and denial of service attacks - explain data interception, theft and the concept of SQL injection - identify the attack at work in an unfamiliar scenario Inside: 7 explanation cells, 2 multiple-choice questions, 3 fill-in-the-blanks cells and 4 written answers. 46 marks, about 75 minutes. Series: J277 1.4 · Network security, part 1 of 3.
WorksheetJ277 1.2 Memory and storage consolidation
Part 6 · J277 1.2.1-1.2.3 · Memory and storage
The end-of-topic checkpoint for memory and storage, pulling together primary storage, virtual memory, storage technologies and data units. Students will: - recall the whole topic without scaffolding - correct flawed statements about memory and storage - calculate capacities and show the working - recommend storage for a stated user and justify it - write a developed answer under exam conditions Inside: 3 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 8 written answers. 54 marks, about 75 minutes. Series: J277 1.2.1-1.2.3 · Memory and storage, part 6 of 6.
WorksheetJ277 1.2.3 Data units and capacity
Part 5 · J277 1.2.1-1.2.3 · Memory and storage
Data units and capacity calculations, using decimal arithmetic only so it can be taught before binary conversion. Students will: - explain why computers represent data in binary - order the units from bit to petabyte - convert between adjacent units using the stated convention - calculate a required storage capacity - work out how many files fit in the space available Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 26 marks, about 60 minutes. Series: J277 1.2.1-1.2.3 · Memory and storage, part 5 of 6.
WorksheetJ277 1.2.2 Choosing secondary storage
Part 4 · J277 1.2.1-1.2.3 · Memory and storage
The recommendation question in section 1.2, where the mark depends on fitting the reason to the user. Students will: - explain the six characteristics used to compare storage - apply those characteristics to a scenario - make and justify a storage recommendation - distinguish durability from reliability - replace vague claims with developed reasons Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 32 marks, about 60 minutes. Series: J277 1.2.1-1.2.3 · Memory and storage, part 4 of 6.
WorksheetJ277 1.2.2 Secondary storage technologies
Part 3 · J277 1.2.1-1.2.3 · Memory and storage
The three secondary storage technologies named in OCR J277, kept at the level of detail the specification asks for. Students will: - explain why secondary storage is needed - identify magnetic, optical and solid-state storage - distinguish a storage type from a device or medium - recognise examples of each technology - compare their broad characteristics Inside: 7 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 3 written answers. 23 marks, about 60 minutes. Series: J277 1.2.1-1.2.3 · Memory and storage, part 3 of 6.
WorksheetJ277 1.2.1 Virtual memory
Part 2 · J277 1.2.1-1.2.3 · Memory and storage
What happens when RAM runs short, and why the fix costs performance. Students will: - explain why virtual memory may be needed - identify where virtual memory is located - describe how data moves between RAM and secondary storage - explain why virtual memory is slower than RAM - decide whether a given system can use it Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 29 marks, about 60 minutes. Series: J277 1.2.1-1.2.3 · Memory and storage, part 2 of 6.
WorksheetJ277 1.2.1 Primary storage
Part 1 · J277 1.2.1-1.2.3 · Memory and storage
The opening worksheet on memory and storage, covering RAM, ROM and where cache fits. Students will: - explain why a computer needs primary storage - compare RAM and ROM - describe the purpose of each - explain the role of cache - replace the vague storage answers examiners penalise Inside: 7 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 27 marks, about 60 minutes. Series: J277 1.2.1-1.2.3 · Memory and storage, part 1 of 6.
WorksheetJ277 1.6.1 Core review
Part 5 · J277 1.6 · Digital impacts: Essentials
The core checkpoint completing section 1.6, ending with a supported extended response. Students will: - apply all five issue lenses to unfamiliar scenarios - select the Data Protection, Computer Misuse or Copyright Act correctly - compare open-source and proprietary licences in context - develop both positive and negative impacts - plan an extended response that answers every part of the question Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 6 written answers. 48 marks, about 75 minutes. Series: J277 1.6 · Digital impacts: Essentials, part 5 of 5.
WorksheetJ277 1.6.1 Software licences
Part 4 · J277 1.6 · Digital impacts: Essentials
Open-source and proprietary licensing, treated as a recommendation to be argued rather than a table to be memorised. Students will: - describe the defining features of each licence type - explain benefits and drawbacks for different stakeholders - recommend a suitable licence for a scenario - justify the recommendation from the situation - avoid the common misconceptions about cost and support Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 36 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Essentials, part 4 of 5.
WorksheetJ277 1.6.1 Computer misuse and copyright
Part 3 · J277 1.6 · Digital impacts: Essentials
Two Acts that cover different actions, and the exam skill of deciding which one an incident actually involves. Students will: - explain the Computer Misuse Act 1990 - explain the Copyright, Designs and Patents Act 1988 - decide whether an incident involves one Act, both or neither - distinguish an illegal act from one that is only unethical - justify the decision from what the person actually did Inside: 6 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 33 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Essentials, part 3 of 5.
WorksheetJ277 1.6.1 Data protection
Part 2 · J277 1.6 · Digital impacts: Essentials
The Data Protection Act 2018 at the level OCR requires: purpose and impact, applied to a computing scenario. Students will: - explain the purpose of the Data Protection Act 2018 - describe what responsible data handling looks like - apply the Act to a school computing scenario - explain why security alone is not a complete answer - develop a scenario answer beyond a list of rules Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 37 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Essentials, part 2 of 5.
WorksheetJ277 1.6.1 Impacts on wider society
Part 1 · J277 1.6 · Digital impacts: Essentials
The opening worksheet of OCR J277 section 1.6, introducing the five issue areas the specification asks students to discuss. Students will: - recognise the ethical, legal, cultural, environmental and privacy lenses - identify the people and groups a technology affects - explain positive and negative impacts for each - distinguish what is legal from what is ethical - build a developed, scenario-based paragraph Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 37 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Essentials, part 1 of 5.
WorksheetJ277 1.6.1 Extended response practice
Part 4 · J277 1.6 · Digital impacts: Depth
A workshop on the 8-mark extended-response question, designed to build a process rather than supply a memorised essay. Students will: - use a reliable process for planning an extended answer - diagnose the difference between a weak and a strong response - select accurate knowledge and apply it throughout - cover every requirement printed in the question - self-assess an answer before improving it Inside: 6 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 41 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Depth, part 4 of 4.
WorksheetJ277 1.6.1 Environmental choices
Part 3 · J277 1.6 · Digital impacts: Depth
An extension worksheet that develops the environmental content of section 1.6 across a whole product lifecycle. Students will: - describe environmental impacts from extraction to end of life - explain the mechanism behind an impact rather than naming it - compare short-term and long-term effects - account for the physical infrastructure behind digital services - evaluate realistic mitigations for a product decision Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 36 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Depth, part 3 of 4.
WorksheetJ277 1.6.1 Access, work and culture
Part 2 · J277 1.6 · Digital impacts: Depth
An extension worksheet on cultural impact: who is included, how work changes, and how benefits are distributed. Students will: - explain the digital divide and accessibility - examine remote services and cashless systems - explain how automation changes tasks as well as job totals - consider effects on communication, language and local culture - distinguish effects on people, organisations and communities Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 41 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Depth, part 2 of 4.
WorksheetJ277 1.6.1 Surveillance and privacy
Part 1 · J277 1.6 · Digital impacts: Depth
An extension worksheet on systems that monitor behaviour or decide automatically, for classes ready to evaluate rather than label. Students will: - compare purposes, consequences and safeguards for a monitored system - examine facial recognition, movement tracking and workplace monitoring - explain automated moderation and automated decision making - weigh accuracy, human review and proportionality - move from assertion to evaluation in a written answer Inside: 5 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 40 marks, about 60 minutes. Series: J277 1.6 · Digital impacts: Depth, part 1 of 4.
WorksheetJ277 1.2 Data representation consolidation
Part 5 · J277 1.2.4-1.2.5 · Data representation
The end-of-topic checkpoint for data representation, combining characters, images, sound and compression. Students will: - select the right representation idea for an unfamiliar scenario - calculate text, image and sound file sizes with working shown - compare lossy and lossless compression in context - correct flawed statements about resolution, colour depth and sampling - write a developed answer under exam conditions Inside: 3 explanation cells, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 8 written answers. 56 marks, about 75 minutes. Series: J277 1.2.4-1.2.5 · Data representation, part 5 of 5.
WorksheetJ277 1.2.5 Compression
Part 4 · J277 1.2.4-1.2.5 · Data representation
Lossy and lossless compression, taught as a decision about the file and the user rather than a pair of definitions. Students will: - explain why compression may be needed - distinguish lossy from lossless compression - explain the effect of each on a file - recommend an appropriate type for a scenario - justify the recommendation from the file and the user Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 33 marks, about 60 minutes. Series: J277 1.2.4-1.2.5 · Data representation, part 4 of 5.
WorksheetJ277 1.2.4 Sound
Part 3 · J277 1.2.4-1.2.5 · Data representation
Sampling an analogue wave, and the three factors that decide the size and quality of the result. Students will: - explain how an analogue sound is sampled - define sample rate, bit depth and duration - explain how each affects file size and playback quality - calculate the size of a simple uncompressed sound file - correct the misconception that frequency is what gets sampled Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 33 marks, about 60 minutes. Series: J277 1.2.4-1.2.5 · Data representation, part 3 of 5.
WorksheetJ277 1.2.4 Images
Part 2 · J277 1.2.4-1.2.5 · Data representation
Bitmap images as a grid of pixels, and the two properties examiners most often see confused. Students will: - explain how pixels and binary codes represent an image - distinguish resolution from colour depth - explain how each affects quality and file size - define metadata and give suitable examples - calculate the size of an uncompressed image file Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 32 marks, about 75 minutes. Series: J277 1.2.4-1.2.5 · Data representation, part 2 of 5.
WorksheetJ277 1.2.4 Characters and text
Part 1 · J277 1.2.4-1.2.5 · Data representation
How text is stored in binary, covering character sets, ASCII, Unicode and text-file size. Students will: - explain what a character set is - explain how characters are represented in binary - relate bits per character to the number of available codes - compare ASCII and Unicode - calculate the size of a simple text file Inside: 6 explanation cells, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 5 written answers. 27 marks, about 60 minutes. Series: J277 1.2.4-1.2.5 · Data representation, part 1 of 5.
WorksheetJ277 2.1.2 From problems to algorithms
Part 3 · J277 2.1.1-2.1.2 · Computational thinking and algorithms
Moving between a written problem, OCR Exam Reference Language and runnable Python. Students will: - describe an algorithm as precise, ordered and finite steps - read Exam Reference Language and explain the logic - move between pseudocode and Python for the same algorithm - implement a described algorithm in Python - check an algorithm against its stated purpose Inside: 5 explanation cells, 2 runnable Python tasks, 4 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 17 marks, about 45 minutes. Series: J277 2.1.1-2.1.2 · Computational thinking and algorithms, part 3 of 3.
WorksheetJ277 2.1.2 Inputs, processes, outputs and decomposition
Part 2 · J277 2.1.1-2.1.2 · Computational thinking and algorithms
Defining a problem before writing any code, using the input-process-output model and decomposition. Students will: - define a problem using the input-process-output model - decompose a large problem into smaller testable parts - read and complete a structure diagram - identify inputs, processes and outputs in running code - explain why decomposition makes testing easier Inside: 5 explanation cells, 1 runnable Python task, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 20 marks, about 45 minutes. Series: J277 2.1.1-2.1.2 · Computational thinking and algorithms, part 2 of 3.
WorksheetJ277 2.1.1 Computational thinking
Part 1 · J277 2.1.1-2.1.2 · Computational thinking and algorithms
The opening Paper 2 worksheet, introducing abstraction, decomposition and algorithmic thinking as problem-solving approaches. Students will: - identify each of the three approaches - use each one in a new situation - explain how each helps define or refine a solution - distinguish an approach from a Python feature - justify the approach chosen for a problem Inside: 4 explanation cells, 1 runnable Python task, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 4 written answers. 19 marks, about 45 minutes. Series: J277 2.1.1-2.1.2 · Computational thinking and algorithms, part 1 of 3.
WorksheetJ277 2.4 Boolean logic consolidation
Part 4 · J277 2.4 · Boolean logic
The consolidation worksheet for OCR J277 2.4, bringing gate rules, truth tables, combined expressions and diagrams together in one makerspace scenario. Students will: - translate a stated condition into a Boolean input - choose the operator a described rule needs - complete a truth table for a multi-stage expression - draw a diagram that meets a stated set of requirements - check that every input combination has been considered Inside: 3 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 6 written answers. 24 marks, about 45 minutes. Series: J277 2.4 · Boolean logic, part 4 of 4.
WorksheetJ277 2.4.1 Logic diagrams
Part 3 · J277 2.4 · Boolean logic
Reading and constructing the logic diagrams OCR uses to show how gates are connected. Students will: - trace a Boolean value from input to output through a diagram - write the expression a given diagram represents - draw a diagram for an expression that includes NOT - treat a bracketed section as an input to the next gate - find and correct the fault in an incorrect diagram Inside: 5 explanation cells, 1 multiple-choice question, 1 fill-in-the-blanks cell and 4 written answers. 16 marks, about 45 minutes. Series: J277 2.4 · Boolean logic, part 3 of 4.
WorksheetJ277 2.4.1 Combined Boolean operators and truth tables
Part 2 · J277 2.4 · Boolean logic
Expressions that use more than one operator, worked with intermediate columns so the method stays reliable. Students will: - work outwards from the innermost operation in an expression - use an intermediate column for each smaller part - work out how many rows a truth table needs - complete a truth table for a combined two-input expression - complete a truth table for a three-input expression with brackets Inside: 5 explanation cells, 2 multiple-choice questions, 2 fill-in-the-blanks cells and 2 written answers. 23 marks, about 45 minutes. Series: J277 2.4 · Boolean logic, part 2 of 4.
WorksheetJ277 2.4.1 Boolean operators and truth tables
Part 1 · J277 2.4 · Boolean logic
The first Boolean logic worksheet for OCR J277 2.4.1, covering the three required operators and the truth tables that describe them. Students will: - state what a Boolean value is and where a computer uses one - describe what AND, OR and NOT each do to their inputs - recognise the symbol for each of the three required gates - complete a truth table for a single operator - apply the operators to a stated real condition Inside: 4 explanation cells, 3 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 11 marks, about 45 minutes. Series: J277 2.4 · Boolean logic, part 1 of 4.
WorksheetJ277 2.2 Programming fundamentals consolidation
Part 5 · J277 2.2.3 · Applied programming
The final Paper 2 programming checkpoint, combining constructs, strings, arrays, records, files, subprograms, random numbers and SQL. Students will: - select and combine techniques for an unfamiliar requirement - total a two-dimensional array - combine strings and random numbers in one program - debug faults in boundaries, accumulation and returns - justify the techniques chosen Inside: 5 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions and 4 written answers. 33 marks, about 60 minutes. Series: J277 2.2.3 · Applied programming, part 5 of 5.
WorksheetJ277 2.2.3 Random number generation
Part 4 · J277 2.2.3 · Applied programming
Random number generation in an algorithm, and turning a requirement into the correct inclusive bounds. Students will: - use random.randint() with inclusive bounds - turn a stated requirement into the correct bounds - map random integers onto outcomes - generate several values in one program - explain why the program behaves differently each run Inside: 5 explanation cells, 3 runnable Python tasks, 2 multiple-choice questions and 2 written answers. 14 marks, about 45 minutes. Series: J277 2.2.3 · Applied programming, part 4 of 5.
WorksheetJ277 2.2.3 SQL
Part 3 · J277 2.2.3 · Applied programming
SQL at the level OCR J277 requires: SELECT, FROM and WHERE, written against a sample table. Students will: - build a query as SELECT fields, FROM table, then WHERE condition - quote string values and leave numerical values unquoted - use the wildcard when a question asks for all fields - join two conditions with AND or OR as the wording requires - predict the records a query returns, and correct one that is wrong Inside: 4 explanation cells, 4 multiple-choice questions, 2 fill-in-the-blanks cells and 4 written answers. 25 marks, about 45 minutes. Series: J277 2.2.3 · Applied programming, part 3 of 5.
WorksheetJ277 2.2.3 File handling
Part 2 · J277 2.2.3 · Applied programming
Persistent storage taught in OCR Exam Reference Language first, then the same open, read, write and close operations in runnable Python. Students will: - explain why a file keeps data that a variable does not - use open, readLine, writeLine and close in the right order - read every line of a file using endOfFile in a loop - carry the same operations across into Python, with the mode strings supplied - write a file-handling procedure that uses the parameters it is given Inside: 8 explanation cells, 2 runnable Python tasks, 1 multiple-choice question, 3 fill-in-the-blanks cells and 1 written answer. 21 marks, about 45 minutes. Series: J277 2.2.3 · Applied programming, part 2 of 5.
WorksheetJ277 2.2.3 Two-dimensional arrays and records
Part 1 · J277 2.2.3 · Applied programming
Two-dimensional arrays and records, the two structures OCR uses for grids and for entities. Students will: - create a two-dimensional structure and access it by row and column - update a value at a given grid position - process every value with nested loops - represent one entity as a record with named fields - choose between a grid and a record for a requirement Inside: 6 explanation cells, 4 runnable Python tasks, 2 multiple-choice questions, 1 fill-in-the-blanks cell and 2 written answers. 23 marks, about 60 minutes. Series: J277 2.2.3 · Applied programming, part 1 of 5.