Community resourceWorksheet

OCR H446 1.2.3 Agile methodologies, XP and RAD

Part 2 of 6 · 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.

Shared by Coding PathwayVerified teacher

  • 13 cells
  • About 45 minutes
  • CC BY-SA 4.0
  • Shared 31 Aug 2026
  • Updated 15 Sept 2026

Preview

The whole resource, exactly as a class sees it. Answers and marking are held back.

Agile methodologies, extreme programming and RAD

Agile approaches, extreme programming (XP) and rapid application development (RAD) can all respond to change, but they are not interchangeable names. This worksheet explains what each approach produces, how feedback is used and what conditions are needed for it to work well.

Keep the boundaries visible

Agile, extreme programming and RAD boundariesRelated ideas: different boundaries and emphasis AGILE: family of iterative approachesshort iterationdelivers a usable incrementreview + feedbackreprioritises later work EXTREME PROGRAMMING (XP)a named agile approach with engineering practicespair programmingrefactoringfrequent testingcollective ownershipsmall releases RADrapid successive prototypes1 build prototype2 user evaluates3 refine and repeatrequires regular user access All respond to change, but compare the process, emphasisand conditions each approach requires.

Agile development describes a family of approaches that build software in short iterations. Each iteration plans, develops and tests a small usable increment. Stakeholders review the working software, and their feedback helps the team choose or reprioritise later work.

Extreme programming (XP) is the agile approach named specifically in OCR's clarification. It combines small releases and close feedback with engineering practices such as pair programming, frequent or test-driven testing, refactoring, collective code ownership and continuous integration. These practices aim to keep frequently changed code reliable and maintainable.

Rapid application development (RAD) quickly produces successive prototypes. End users evaluate each prototype, and the team refines the requirements and design in response. RAD particularly emphasises rapid prototyping and user evaluation.

All three can involve iteration and feedback. Their purpose and emphasis are not identical.

Worked context: volunteer rota service

A charity needs a rota service. Its coordinator can review working software every two weeks, and the event rules change during the year.

An agile team could deliver login and basic shift booking first. The coordinator reviews that usable increment, and the team uses the feedback to decide what to build next. This reduces the chance of completing a large system based on old requirements. It relies on regular decisions from the charity and good team communication.

XP practices can support the frequent code changes. Automated tests can reveal when a change breaks existing behaviour. Refactoring keeps the code easier to change, while pair programming allows two developers to discuss and review the same work. These practices take time and require discipline; naming a practice without explaining its effect is not enough.

Multiple choice1 mark

Which statement is most accurate?

  • AAgile means one fixed methodology with one compulsory set of roles
  • BXP is a named agile approach whose practices support frequent, high-quality change
  • CRAD means skipping user feedback so coding is faster
  • DPair programming alone proves that every project uses XP
Fill in the blanks3 marks
Agile delivers small gap 1 and reprioritises from feedback. XP adds engineering gap 2 such as refactoring and pair programming. RAD rapidly refines successive gap 3 with users.
  • increments
  • practices
  • prototypes
  • waterfalls
Written answer7 marks

Explain how two XP practices could help a team maintain a codebase that changes frequently. State one cost or condition that could limit the benefit.

For each practice, explain what the developers do and how this affects the code. Then add one realistic limitation.

Students type their answer here.

RAD: learn from rapid prototypes

A museum needs a touch-screen guide before an exhibition opens. Staff cannot yet describe the best screen layout, but they can test a prototype twice each week.

With RAD, the team quickly produces a prototype. Museum staff try it and comment on navigation, text size and media placement. The team then refines the prototype and repeats the process until an acceptable solution is produced.

This suits unclear interface requirements and available users. It is less suitable when users cannot attend reviews, when the system cannot be divided into manageable prototypes, or when rapid visible progress hides difficult safety, performance or integration work.

Written answer6 marks

For the museum guide, explain one difference between an agile increment and a RAD prototype. Then explain how one XP practice could improve the code produced in either approach.

An increment is intended to be a usable part of the product. A prototype is produced quickly so users can evaluate and refine requirements. Use that distinction in your answer.

Students type their answer here.

Apply the distinctions

The remaining questions use less familiar projects. Keep agile iteration, XP engineering practices and RAD prototyping separate, even when more than one could contribute to the same project.

Written answer8 marks

A small distributed team is building safety-control software. The safety rules are fixed, the client cannot attend frequent reviews and the final code must respond quickly and reliably. Evaluate the suitability of agile with XP practices and of RAD for this project.

Consider team collaboration, access to the client, fixed requirements, code quality and the limits of rapid prototyping. Give a balanced conclusion rather than choosing from one clue.

Students type their answer here.

Written answer5 marks

Correct this advice: ‘Use RAD whenever the deadline is short because RAD just means coding faster. XP is separate from agile because it uses pair programming.’

Give an accurate description of RAD, an accurate relationship between XP and agile, and one condition needed by each approach.

Students type their answer here.

Fill in the blanks4 marks
Agile is a checkpoint gap 1 of iterative approaches. XP is a named agile checkpoint gap 2 that uses engineering practices. RAD develops rapid successive checkpoint gap 3 and depends on regular user checkpoint gap 4.

Review your understanding

Check that you can explain what agile, XP and RAD do, distinguish a usable increment from a prototype, and connect each claimed benefit to the people, feedback or engineering practice that produces it.