GCSE Computer Science
Numeracy is heavy and specific: learners convert between denary, binary and hexadecimal, add in binary, work with base 2 storage units, calculate image, sound and compressed file sizes and routing costs, and reason with truth tables and DIV and MOD. Literacy centres on close reading of the Unit 2 scenario and requirements, precise technical vocabulary, short and extended judgement answers in Unit 1, and code annotation and test commentaries. The single biggest thing Key Stage 3 should build is fluent place value in base 2 and base 16, so that storage and file size calculations become routine.
- Awarding body
- WJEC
- Level
- Level 1 and Level 2
- First taught
- September 2025
- Amount of literacy work
- Medium
- Amount of numeracy work
- High
- Specification
- Open the specification
How this qualification is assessed
- Unit 1: Understanding Computer Science: Digital examination 1 hour 30 minutes, 50%, 80 marks
- Unit 2: Computer Programming: On-screen examination based on a pre-released brief, 2 hours, 50%, 80 marks, set and marked by WJEC
Skills that use Vocabulary, spelling, grammar
-
Technical vocabulary and acronyms
Learners must recall and use precise technical terms and a long list of acronyms (CPU, ALU, RAM, TCP, HTTPS, DNS and more) and show understanding of software development terminology. Identifiers in code must also be spelt consistently to work.
Literacy: Vocabulary, spelling, grammar
Getting pupils ready
- Year 7
- Pupils build a Computer Science glossary of hardware words such as processor, input, output and storage, and spell each from memory in a weekly five-word quiz.
- Year 8
- Pupils expand acronyms such as CPU, RAM, ROM and USB and use each one correctly in a sentence about a real device in the classroom.
- Year 9
- Pupils rewrite a vague answer such as 'the computer gets faster' using precise terms like clock speed, cores and cache, correcting any misspelt terms.
Show the specification wording and the LNF statements
Where it is in the specification: Unit 2, Section 2.4.2 Refinement and evaluation, page 26
“demonstrate an understanding of the technical terminology/concepts used during software development”
Progression step 3
I can use varied, appropriate and precise vocabulary including area of learning and experience/discipline-specific words for different purposes.
I can use strategies to correctly spell polysyllabic, complex and irregular words in the context of each area of learning and experience.
Progression step 4
I have experienced a range of area of learning and experience/discipline-specific and general academic vocabulary, and can use them in my own communication.
I can use a variety of strategies and resources to spell familiar and unfamiliar vocabulary and area of learning and experience/discipline-specific words correctly.
Progression step 5
I can use a range of discipline-specific and general academic vocabulary accurately and precisely.
I can use strategies to spell discipline-specific and general academic words in appropriate contexts.
-
Annotating code, writing test commentaries and refining
Learners annotate code so a competent third party can follow it, present test outcomes with commentaries, and explain and evaluate the changes they make when refining a solution. Test plans must use typical, extreme and erroneous data.
Literacy: Proofreading, editing and improving, Planning and organising for different purposes, audiences and context, Vocabulary, spelling, grammar
Getting pupils ready
- Year 7
- Pupils add comments to their Scratch or Python game explaining what each part does, then swap with a partner who checks the comments make sense without running the code.
- Year 8
- Pupils complete a test table for a number-guessing program using typical, extreme and wrong inputs and write one sentence explaining each result.
- Year 9
- Pupils fix a bug in a given Python program and write a short commentary saying what went wrong, what they changed and how they retested it.
Show the specification wording and the LNF statements
Where it is in the specification: Unit 2, Sections 2.3.1 and 2.4.1, pages 25 to 26
“present test outcomes with detailed and informed commentaries”
Progression step 3
I can reflect on, edit and redraft to improve the quality of my expression, and use a range of strategies to ensure greater clarity.
I can explore different ways to plan, draft and present my work appropriately.
I can present my work appropriately in digital contexts.
Progression step 4
I can improve writing through independent review and redrafting.
I can select and use appropriate strategies to plan and develop my writing for different purposes and audiences.
I can present my work appropriately in digital contexts using appropriate digital conventions, e.g. thumbnails, language preferences.
Progression step 5
I can improve the content, structure and accuracy of my writing through critical reflection, review and editing, responding constructively to feedback.
I can summarise confidently, adapting style and form for the reader or intended audience and purpose for writing.
I can understand and use formal conventions of language in a range of purposes, making effective use of reference tools and accuracy aids.
Good to know
- No marks are set aside for spelling, punctuation and grammar. The assessment objectives on page 28 cover only knowledge (AO1), application (AO2) and analysis (AO3), so accuracy of language is not separately credited.
- Both units are answered on screen, page 5: Unit 1 is a "Digital examination: 1 hour 30 minutes" and Unit 2 is an "On-screen examination based on a pre-released brief: 2 hours". Pupils need to type extended answers and calculations.
- The specification does not say whether a calculator is allowed in either unit, so centres should check the WJEC instructions for each series. Pupils should be able to do binary, hexadecimal and storage calculations by hand.
- No notes are allowed into the Unit 2 examination, page 28: "learners are not permitted to take any prompts or notes into the examination." A clean copy of the pre-release is provided.
- Unit 1 mixes question types, page 5: "Questions requiring objective responses, short and extended answers."
- Storage units use 1,024, not 1,000, page 13: "kilobyte (i.e. 1,024 bytes)". Pupils who learn 1,000 in Science or Mathematics need the difference made explicit.
- Appendix B, pages 34 to 36, fixes the operators and pseudocode conventions used in questions: "Logical operators AND OR NOT XOR will be in upper case." DIV and MOD are defined with worked examples such as "11 MOD 2 = 1".
- Appendix A, page 32, marks the numeracy strands for geometry and measurement and for statistics and probability as N/A for both units, so there is no graphing or statistics demand.
Links with other qualifications
Place value, powers, ratio and percentage reduction are taught in Mathematics, so agreeing shared language (for example 'column value' and 'simplest form') with the Mathematics department in Years 7 to 9 will help pupils transfer these skills to binary and file size work.
Source: WJEC GCSE Computer Science specification, teaching from 2025, for award from 2027, Version 3, September 2025.