IB Computer Science HL · Internal Assessment

Computational Solution Hub

Your IA is one computational solution assessed across five criteria. For HL it contributes 20% of the final subject result. Use this hub to keep the problem, design, development, testing, evaluation and submission evidence connected.

Course home 2027 case study

Overview

30 marks · five connected criteria

2 / 7

A · 4 marks

Problem specification

Describe measurable solution requirements, state appropriate success criteria, and explain the computational context. Recommended: about 300 words.

B · 4 marks

Planning

Decompose the problem reasonably and construct a plan that addresses the success criteria. Recommended: about 150 words.

C · 6 marks

System overview

Construct a complete system model, algorithms and a testing strategy aligned to the success criteria. Recommended: about 150 words.

D · 12 marks

Development

Deliver a fully functional product using appropriate techniques; evaluate implementation choices and justify testing effectiveness. Recommended: about 1,000 words.

E · 4 marks

Evaluation

Evaluate the extent to which success criteria were met and justify meaningful, feasible improvements. Recommended: about 400 words.

Connection ruleCriterion A’s success criteria should remain visible through B planning, C testing design, D development/testing and E evaluation.

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Criteria A–C

Build a testable plan before coding drifts

3 / 7

A — Problem specification

Problem requirements are measurable rather than vague.

Success criteria can be tested later.

Computational context is explained and appropriate.

B — Planning

Problem is decomposed into essential components.

Plan addresses every success criterion.

Chronology includes design, development, testing and evaluation.

C — System overview

System model shows components, relationships, rules and UI design clearly enough for another person to understand/recreate the system.

Algorithms for important components are represented clearly.

Testing strategy aligns with the success criteria and includes valid, extreme and invalid/unexpected cases where appropriate.

Do not treat C as screenshots of finished codeThe system overview is design evidence: model + algorithms + testing strategy prepared to guide development.

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Criterion D

Development is the largest criterion

4 / 7

Product and techniques

Product is fully functional against the intended requirements.

Documentation highlights important code excerpts and explains the algorithmic thinking.

Technique choices are evaluated, not merely named.

Testing evidence

Testing addresses correctness, reliability and efficiency where relevant.

Documentation describes and justifies the testing strategy’s effectiveness.

Video demonstrates functionality and examples of the testing strategy.

Technique levelThe IA criteria are the same at SL and HL; techniques should fit the problem and success criteria. Unnecessary complexity is not automatically better.

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Criterion E + files

Evaluate, then package the evidence correctly

5 / 7

E — Evaluation

Each success criterion is evaluated using evidence from the product/testing.

Improvements are specific, meaningful and feasible.

Improvements are justified by how they benefit the product.

Final submission: three files

1. Documentation PDF — five criterion sections, total ≤ 2,000 words; overall word count on the first page.

2. Video — ≤ 5 minutes; demonstrates full functionality and examples of testing.

3. Appendices PDF — full source code plus referenced supporting resources.

Word limit is hardIf the documentation exceeds 2,000 words, moderators stop reading after the limit.

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Year 2 course checkpoints

IA runs in parallel with the syllabus

6 / 7

L1–L9

Refine A/B/C. Keep the problem measurable, the plan aligned to success criteria, and the system/testing design usable for development.

L10–L32

Criterion D main development. Implement, test and keep an evidence log of important decisions/techniques.

L33–L39

Wrap D: documentation evidence, testing explanation, video and appendix preparation.

L40–L45

Criterion E, final consistency checks, authenticity checks and course submission.

L46–L55

IA is normally complete; homework shifts toward Paper 1, Paper 2 and the 2027 case study.

Homework strategyWhile the IA is active, it is the main homework workload. Short syllabus retrieval continues so exam knowledge is not allowed to decay.

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Authenticity and final check

Your solution must remain your own work

7 / 7

Academic integrity

All external information/code/resources are acknowledged appropriately.

Any use of AI tools is acknowledged; AI does not replace your own decision-making, algorithmic thinking or authorship.

Full submitted source code is readable and matches the product.

Teacher guidance

You should discuss the IA with your teacher and ask questions. The teacher may read and advise on one draft but does not edit it for you; the next version submitted to the teacher is the final version.

Be ready to explain your code, design choices, testing and source use as part of authenticity checking.

Before final submissionOpen all three files, verify links/references, confirm the video is ≤5 minutes, confirm documentation is ≤2,000 words, and make sure the appendix contains the full source code.

Designed by David Xu

Educators and students are welcome to use these materials for non-commercial teaching and learning with attribution. Please share the original link when possible. Reposting, redistributing modified copies, removing attribution, or commercial use requires prior permission.

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