12. Software Development
Program development life cycle, program design tools, program testing, test data and maintenance.
Statometer60CoreNext Paper 284%Everything for this topic — study hub
AS Level · 9618 · Paper 2
This topic is rows 36–39 of the study route.Open it on your study route
Statometer — what 33 real papers say about this topic and each of its 4 syllabus bullets
Core · #10 of 12 in AS Level · recomputed with every new session
A regular, well-paid topic — you cannot afford a gap here.
- Next Paper 2
- 84%
- 8 in 10 chance it is set
- Marks a paper
- 13 / 75
- 17% of Paper 2 · fair share 25%
- Appeared in
- 28 / 33
- Paper 2 sittings 2021–2026
- Last set
- May/Jun 2026
- 9618/23 · Q3 · 11 marks · 11-series streak
What the papers say
- Set in 28 of 33 Paper 2 sittings — about 8 papers in 10.
- Worth about 13 marks a paper (17% of Paper 2).
- Last set May/Jun 2026 · 9618/23 · Q3 for 11 marks — in the most recent series.
- Set in each of the last 11 series without a miss.
- Steady at around 14.2 marks a paper year on year.
- Lives on “State” and “Complete” — 73% of its questions: short, precise answers in syllabus words.
- 63% of its questions involve a diagram, table or figure — practise with pen and paper.
- 67% of its questions are set out as code, pseudocode or a table to complete.
- Its biggest question so far: 27 marks (May/Jun 2026 · 9618/22 · Q1).
- Inside the topic, §12.2 Program design carries the most marks (38%) and §12.3 Program maintenance the least (7%).
- It is examined mostly as AO2 (Apply & analyse, 74%), the rest AO3 (26%) — you must apply it to the given data or scenario — work it out, trace it, explain it in context.
- The examiner has commented on 42 of its questions — read “What the examiner said” before you practise.
Command words
Share of questions using the word (a question can use several). What each wants →
Question shapes
- ≤ 6 mk17
- 7–9 mk20
- 10–12 mk22
- 13–15 mk5
- 16+ mk3
Average 9.3 marks a question · 63% with a figure or table · 67% with code · biggest 27 marks
Assessment objectives — how it is examined
Every part of every current-syllabus question filed under Cambridge's AO1 / AO2 / AO3 (from its command word and what it asks you to do), so you know whether this topic pays for definitions, for applying, or for judging and building.
- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
Paper 2 as a whole
| Paper 2 | Syllabus | Measured |
|---|---|---|
| AO1 Knowledge & understanding | 0% | 0% |
| AO2 Apply & analyse | 40% | 45% |
| AO3 Design, program & evaluate | 60% | 55% |
Syllabus = Cambridge's grid; measured = the bank's current-syllabus papers.
Inside the topic — every syllabus bullet, measured
Each part of each question is filed under the bullet it examines; the numbers are per Paper 2 sitting, exactly like the topic's. Open a bullet for its own Statometer.
12.1Program development life cycle#11 of 14 on Paper 2Regular · 4355% next paper2.9 marks18/33 sittings↗ May/Jun 2026Regular · 4355%
2.9 · 20% of topic18/33May/Jun 2026latest series · ↗Set most sessions for a few marks; know the definition and one example.Syllabus: its purpose; waterfall, iterative and RAD models with their principles, benefits and drawbacks; the analysis, design, coding, testing and maintenance stages
- Next Paper 2
- 55%
- 5 in 10
- Marks a paper
- 2.9
- 4% of the paper · 20% of the topic
- Asked in
- 18 / 33
- Paper 2 sittings · 28 questions
- Last asked
- May/Jun 2026
- 9618/23 · Q3 · 9.5 marks · 4-series streak
- Asked in 18 of 33 Paper 2 sittings — about 5 papers in 10.
- About 2.9 marks a paper (4% of Paper 2; 20% of the topic's marks across its 4 bullets).
- Last asked May/Jun 2026 · 9618/23 · Q3 (9.5 marks) — in the most recent series.
- Asked in each of the last 4 series.
- Rising: 2 → 3.7 marks a paper.
- Usually “Identify” or “State”: short, precise answers in syllabus words.
- Biggest chunk of marks so far: 9.5 in May/Jun 2026 · 9618/23 · Q3.
- It is examined almost entirely as AO2 (Apply & analyse, 83%) — you must apply it to the given data or scenario — work it out, trace it, explain it in context.
Last 12 sittings↗ RisingAssessment objectives
AO2 83%AO3 17%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- Identify68%
- State64%
- Complete54%
- Give25%
12.2Program design#7 of 14 on Paper 2Core · 5963% next paper4.5 marks20/33 sittings↗ May/Jun 2026Core · 5963%
4.5 · 38% of topic20/33May/Jun 2026latest series · ↗A regular earner inside the topic — most papers touch it.Syllabus: structure charts (purpose, construction, parameters between modules, deriving pseudocode) and state-transition diagrams
- Next Paper 2
- 63%
- 6 in 10
- Marks a paper
- 4.5
- 6% of the paper · 38% of the topic
- Asked in
- 20 / 33
- Paper 2 sittings · 42 questions
- Last asked
- May/Jun 2026
- 9618/23 · Q3 · 1.5 marks · 6-series streak
- Asked in 20 of 33 Paper 2 sittings — about 6 papers in 10.
- About 4.5 marks a paper (6% of Paper 2; 38% of the topic's marks across its 4 bullets).
- Last asked May/Jun 2026 · 9618/23 · Q3 (1.5 marks) — in the most recent series.
- Asked in each of the last 6 series.
- Rising: 2.6 → 5.3 marks a paper.
- Usually “State” or “Complete”: short, precise answers in syllabus words.
- Biggest chunk of marks so far: 11.5 in May/Jun 2026 · 9618/22 · Q1.
- It is examined mostly as AO2 (Apply & analyse, 67%), the rest AO3 (33%) — you must apply it to the given data or scenario — work it out, trace it, explain it in context.
Last 12 sittings↗ RisingAssessment objectives
AO2 67%AO3 33%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- State57%
- Complete48%
- Identify41%
- Explain26%
12.3Program testing#10 of 14 on Paper 2Regular · 5061% next paper3.4 marks21/33 sittings↗ May/Jun 2026Regular · 5061%
3.4 · 35% of topic21/33May/Jun 2026latest series · ↗Set most sessions for a few marks; know the definition and one example.Syllabus: syntax, logic and run-time errors; dry run, walkthrough, white-box, black-box, integration, alpha, beta, acceptance, stub testing; test strategy, test plans and test data
- Next Paper 2
- 61%
- 6 in 10
- Marks a paper
- 3.4
- 5% of the paper · 35% of the topic
- Asked in
- 21 / 33
- Paper 2 sittings · 40 questions
- Last asked
- May/Jun 2026
- 9618/22 · Q1 · 12 marks · 11-series streak
- Asked in 21 of 33 Paper 2 sittings — about 6 papers in 10.
- About 3.4 marks a paper (5% of Paper 2; 35% of the topic's marks across its 4 bullets).
- Last asked May/Jun 2026 · 9618/22 · Q1 (12 marks) — in the most recent series.
- Asked in each of the last 11 series.
- Rising: 2.5 → 3.9 marks a paper.
- Usually “State” or “Complete”: short, precise answers in syllabus words.
- Biggest chunk of marks so far: 12 in May/Jun 2026 · 9618/22 · Q1.
- It is examined almost entirely as AO2 (Apply & analyse, 76%) — you must apply it to the given data or scenario — work it out, trace it, explain it in context.
Last 12 sittings↗ RisingAssessment objectives
AO2 76%AO3 24%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- State48%
- Complete38%
- Identify35%
- Describe33%
12.3Program maintenance#14 of 14 on Paper 2Occasional · 1119% next paper0.4 marks7/33 sittings→ May/Jun 2025Occasional · 1119%
0.4 · 7% of topic7/33May/Jun 20252 series ago · →Rotated in occasionally — the bullet students skip and then meet.Syllabus: perfective, adaptive and corrective maintenance; analysing and amending an existing program
- Next Paper 2
- 19%
- 1 in 5 or less
- Marks a paper
- 0.4
- 1% of the paper · 7% of the topic
- Asked in
- 7 / 33
- Paper 2 sittings · 12 questions
- Last asked
- May/Jun 2025
- 9618/22 · Q1 · 4 marks · 2 series ago
- Asked in 7 of 33 Paper 2 sittings — roughly one paper in 5.
- About 0.4 marks a paper (1% of Paper 2; 7% of the topic's marks across its 4 bullets).
- Last asked May/Jun 2025 · 9618/22 · Q1 (4 marks), 2 seriess ago.
- Usually “State” or “Explain”: short, precise answers in syllabus words.
- Biggest chunk of marks so far: 4 in May/Jun 2025 · 9618/22 · Q1.
- It is examined almost entirely as AO2 (Apply & analyse, 96%) — you must apply it to the given data or scenario — work it out, trace it, explain it in context.
Last 12 sittings→ SteadyAssessment objectives
AO2 96%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- State83%
- Explain42%
- Give42%
- Describe25%
24% of the topic's marks sit in question parts that belong to another topic (scenario questions cross sections) or that no bullet claims; they count for the topic, not for a bullet.
Marks a paper, year by year
Grey years are the previous syllabus (2015–2021, 28 questions) — history, not counted in the rates.
By exam series
- May/Jun15/18 · 12.1 mk
- Oct/Nov13/15 · 13.3 mk
What you need to know4syllabus §12.1, §12.2, §12.3
- 12.1Program development life cycle — its purpose; waterfall, iterative and RAD models with their principles, benefits and drawbacks; the analysis, design, coding, testing and maintenance stages
- 12.2Program design — structure charts (purpose, construction, parameters between modules, deriving pseudocode) and state-transition diagrams
- 12.3Program testing — syntax, logic and run-time errors; dry run, walkthrough, white-box, black-box, integration, alpha, beta, acceptance, stub testing; test strategy, test plans and test data
- 12.3Program maintenance — perfective, adaptive and corrective maintenance; analysing and amending an existing program
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Infographics3draw these the way the examiner expects · download as PNG
Choosing test data
Waterfall, iterative & RAD
Testing & maintenance
Key terms13use these exact words in the exam
Dotted terms are defined in the glossary.
Code help2referenced to the Cambridge pseudocode guide
Test data table for a validation routine
textRule: mark must be an integer 0–100 Type Test value Expected Normal 56 accepted Extreme 0 / 100 accepted Boundary -1 / 101 rejected Abnormal "abc" / 3.5 rejected
FUNCTION LookupPrice(Code : STRING) RETURNS REAL// STUB — real database lookup not written yetRETURN 9.99ENDFUNCTIONDECLARE Total : REALTotal ← LookupPrice("A1") * 3OUTPUT "Total (using stub) = ", Total
Playground examples5runnable programs for this topic
- Run
Stepwise refinement — a bank menu built from modules
The main program only shows the menu and CALLs procedures; each module does one job (a structure chart in code).
- Run
Trace table practice
A typical dry-run question. Run it, then open the Trace table tab and check it against your own table.
- Run
Normal, boundary and abnormal test data
Drive a function with each kind of test data and check the results against what you expected.
- Run
Validation loop — range and type checks
Keep asking until the input is a whole number between 1 and 100. try/except catches the ValueError from int().
- Run
ISBN-13 check digit
Weights 1 and 3 alternate; the check digit makes the total a multiple of 10.
Also for this topic: 2 Java programs · 3 VB.NET programs in the browser compilers.
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