WJEC A-level Computer Science: five units, the project and 2027 dates

WJEC A-level Computer Science: the specification

WJEC GCE AS and A level Computer Science is regulated by Qualifications Wales and is not available to centres in England; the English brand Eduqas runs a separate A level. The specification (version 2, March 2019) was first taught in 2015. AS awards come from Units 1 and 2, and the full A level from all five units.

WJEC A-level Computer Science units

Dates are from WJEC's final summer 2027 timetable. Unit 5 is a project in which you discuss, investigate, design, prototype, refine, implement, test and evaluate a computerised solution. See our WJEC A-level timetable 2027 for every paper and the results day.

What each unit covers

• AS 1: hardware and communication, logical operations, data transmission, data representation and types, data structures, organisation of data, database systems, the operating system, and algorithms and programs.
• AS 2: a series of set tasks completed on screen that test practical programming, in Visual Basic.NET, Python or Java.
• A2 3: data structures, logical operations, algorithms (including recursion) and programs, principles of programming, systems analysis and design, software engineering, program construction, and economic, moral, legal, ethical and cultural issues.
• A2 4: hardware and communication, data transmission, data representation (including floating point), organisation and structure of data, databases and distributed systems, the operating system, types of software system and data security and integrity.

Across the A level 35% of marks are AO1 (knowledge), 35% AO2 (applying it) and 30% AO3 (design, program and evaluate).

Worked examples in WJEC style

Two's complement

Write −45 in 8-bit two's complement. Start with +45, which is 00101101, flip every bit to 11010010, then add 1:

So −45 is 11010011. Check: the top bit is worth −128, and −128 + 64 + 16 + 2 + 1 = −45.

Binary search

A sorted list holds 1,000 items. Each comparison halves the remaining items, so at most ⌈log₂(1001)⌉ comparisons are needed:

A linear search might need up to 1,000. This difference is what you should state when asked to compare algorithms.

WJEC A-level Computer Science grades

Unit results are scored on a uniform mark scale, added up and graded. An AS has 200 uniform marks in total and the A level 500. Grades run A to E at AS and A* to E at A level; below E is U.

An A* needs an A overall (400 uniform marks) and at least 90% of the uniform marks for the A2 units, which is 270 out of 300. See A-level grades explained.

Use the daily paper as a short timed mock for WJEC A-level Computer Science

Uni-Sine publishes a new free daily paper on each track: A-level Computer Science. It is a short timed mock: 8 questions worth 25 to 35 marks, marked instantly, with worked answers. It is not a full exam paper and it is not written by the exam board, so use it as a quick timed practice test alongside the board's own specimen and past papers.

• What it covers well: processor architecture, databases and SQL, number representation and floating point, data structures, networking, recursion, object-oriented programming and searching and sorting, which cover much of Units 1, 3 and 4.
• What it does not cover: the on-screen programming of Unit 2 and the Unit 5 project, which are 35% of the grade between them. Write real programs for those.

One daily paper keeps theory sharp. Spend the rest of the week coding and building your Unit 5 project.

Exam answers

Uni-Sine does not publish official answers, past paper answers or mark schemes from the exam board. The answers and a worked mark scheme for each daily paper come with that day's paper once it is marked, so you can see where every mark was won or lost.

Common mistakes in WJEC A-level Computer Science

• Leaving Unit 5 late. It is a fifth of the grade and needs documented stages.
• Practising Unit 2 on paper. It is on-screen, so write code in your chosen language.
• Confusing Wales and Eduqas papers. The Wales specification has different units and lengths.
• Stopping at "it is faster". Compare algorithms with the number of steps.

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UK · A-levelWJEC A-level Computer Science grade boundaries 2026WJEC A-level Computer Science 2026 boundaries: raw marks for the three exams, the on-screen paper and the programmed solution, against the fixed UMS scale.