GCSE Computer Science · Resource

GCSE Revision Workbook

A structured revision resource covering all major GCSE Computer Science topics — with practice questions, key vocabulary, and revision activities designed around the OCR specification.

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What this covers

✓Core theory: algorithms, binary, networks, hardware

✓Key vocabulary for every major topic

✓Practice questions with mark scheme answers

✓OCR pseudocode reference and practice exercises

✓Revision strategies for learners who find standard note-taking hard

How to use this workbook effectively

A revision workbook only works if you use it actively — not just read it. The goal is to practise retrieving information, not to re-read notes.

Active retrieval

Cover the answer side. Try to recall the answer. Then check. This forces your brain to work harder than reading does, and research consistently shows it leads to better retention.

Spacing and interleaving

Do not revise the same topic for hours in one sitting. Short, focused sessions on different topics across several days is more effective than long sessions on one topic.

Topic 1: Algorithms

Algorithms are sequences of steps that solve a problem. OCR tests searching, sorting, trace tables, and pseudocode.

Term	Definition
Algorithm	A set of step-by-step instructions for solving a problem
Pseudocode	A structured way of writing an algorithm in plain English
Trace table	A table used to track variable values as an algorithm runs
Linear search	Checking each item in order until the target is found
Binary search	Repeatedly halving a sorted list to find the target
Bubble sort	Repeatedly swapping adjacent items until the list is sorted
Merge sort	Recursively splitting and merging sub-lists — more efficient

Topic 2: Binary and data representation

Binary is the foundation of all computer data. Every GCSE paper tests binary conversion, addition, and data types.

Conversion type	Method
Binary → denary	Write column values 128,64,32,16,8,4,2,1. Add positions with a 1.
Denary → binary	Write columns. Work left to right. Subtract if column fits.
Binary addition	Work right to left. 1+1=0 carry 1. Show carries.
Binary → hex	Split into groups of 4. Convert each group (0–9, A–F).
Hex → binary	Convert each hex digit into 4 binary digits.

Topic 3: Networks

Networks appear on both papers. You need to know types, protocols, hardware, and security.

Network types

LAN (Local Area Network) — covers a small area like a school or office. WAN (Wide Area Network) — covers a large geographic area. The internet is the largest WAN.

Key protocols

TCP/IP — the fundamental protocol suite of the internet. HTTP/HTTPS — web browsing. FTP — file transfer. SMTP — email sending. DNS — translating domain names to IP addresses.

Network hardware

Router — connects networks and directs data packets. Switch — connects devices within a network. Wireless access point — enables wireless connection. Firewall — blocks unauthorised traffic.

Network security

Encryption — converting data so it cannot be read without a key. Firewalls — blocking unauthorised access. Passwords and access levels. Regular backups.

Want structured revision support?

Using a workbook alongside 1-to-1 sessions gets the best results — the session explains, the workbook consolidates. Book a revision session to start.

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Frequently asked questions

What topics are in the GCSE CS specification?

OCR GCSE CS covers: computational thinking, algorithms, programming, computer systems, hardware, networks, databases, cybersecurity, data representation, and ethics.

How much does theory count for?

80% of the GCSE grade comes from two written theory papers. The programming project (NEA) is 20%. Many students underestimate how much content is required for the theory papers.

Are there official past papers?

Yes — OCR publishes past papers and mark schemes on their website. Your school should also have access to specimen papers and mark schemes.