20 trace table practice questions for OCR GCSE Computer Science (J277/02), with full completed answers and guidance. All algorithms are written in OCR Exam Reference Language (ERL), exactly as students will see in the exam. Questions progress from simple sequence and selection through to iteration, nested loops, string operations, and array processing — building the skill and confidence needed to tackle trace table questions under exam conditions. Includes: 40 marks across 20 questions, split into three progressive sections Section 1: sequence, selection, if/elseif/else, and AND conditions Section 2: FOR loops, WHILE loops, DO UNTIL, and loops with arrays Section 3: mixed algorithms, string handling, nested loops, and two reverse questions where students read a completed trace and identify the output or an error Full completed trace tables in the answers section — every cell filled, every line numbered Watch out boxes targeting the specific mistakes flagged in OCR examiner reports (wrong line numbers, spurious output, off-by-one errors, stale variable values) A marking note explaining how line number errors are handled — reassuring for students who know how OCR awards follow-through marks A focused exam skill builder — different in format from the topic-based resources in this series, and ideal for targeted practice in the weeks before the exam. Print-ready and suitable for independent revision, homework, or structured classroom practice.

20 exam-style questions on network security for OCR GCSE Computer Science (J277/01), with full answers and guidance. Covers all threats and prevention methods from the J277 specification — malware, phishing, brute-force attacks, denial of service, SQL injection, data interception, firewalls, encryption, anti-malware software, penetration testing, user access levels, passwords, and physical security — with questions modelled on the style and command words used in actual J277 papers: complete the table, identify the error, explain, evaluate, and a scenario-based justify question worth 4 marks. Includes: 40 marks across 20 questions, split into three progressive sections Scenario questions with data tables, matching the real exam format Answers written for students, not teachers — no “award 1 mark” language Watch out boxes targeting the specific misconceptions flagged in OCR examiner reports (including the encryption/interception confusion, the firewall/data-in-transit myth, and DoS attacks being misdescribed as malware) Stretch & challenge questions to deepen understanding without going beyond the spec Print-ready and suitable for independent revision, structured practice, or classroom use.

20 exam-style questions on input validation for OCR GCSE Computer Science (J277/02), with full answers and guidance. Covers all six validation check types tested by OCR — range, type, presence, length, format, and lookup list — with questions modelled on the style and command words used in actual J277 papers: complete the table, identify the error, explain, evaluate, and a scenario-based justify question worth 4 marks. Includes: 40 marks across 20 questions, split into three progressive sections Scenario questions with data tables, matching the real exam format Answers written for students, not teachers — no “award 1 mark” language Watch out boxes targeting the specific misconceptions flagged in OCR examiner reports (particularly the confusion between validation and accuracy, and between check types) Stretch & challenge questions to deepen understanding without going beyond the spec Print-ready and suitable for independent revision, structured practice, or classroom use.

20 exam-style questions on storage for OCR GCSE Computer Science (J277/01), with full answers and guidance. Covers both primary and secondary storage — RAM, ROM, virtual memory, cache, and all three types of secondary storage (magnetic, solid state, and optical) — with questions modelled on the style and command words used in actual J277 papers: complete the table, identify the error, explain, evaluate, and a scenario-based justify question worth 4 marks. Includes: 40 marks across 20 questions, split into three progressive sections Scenario questions with data tables, matching the real exam format Answers written for students, not teachers — no “award 1 mark” language Watch out boxes targeting the specific misconceptions flagged in OCR examiner reports (including the “secondary storage fills when RAM is full” error, the solid state longevity myth, and RAM/ROM confusion in virtual memory) Stretch & challenge questions to deepen understanding without going beyond the spec Print-ready and suitable for independent revision, structured practice, or classroom use.

20 exam-style questions on operating systems for OCR GCSE Computer Science (J277/01), with full answers and guidance. Covers both OS functions and utility software — user interface, memory management, peripheral management, user management, file management, defragmentation, encryption software, and data compression — with questions modelled on the style and command words used in actual J277 papers: complete the table, identify the weakness, describe, explain, evaluate, and a scenario-based justify question worth 4 marks. Includes: 40 marks across 20 questions, split into three progressive sections Scenario questions with data tables, matching the real exam format Answers written for students, not teachers — no “award 1 mark” language Watch out boxes targeting the specific misconceptions flagged in OCR examiner reports (including peripheral management described too vaguely, defragmentation described as creating more space, lossy compression on text files, and utility software confused with the OS itself) Stretch & challenge questions to deepen understanding without going beyond the spec Print-ready and suitable for independent revision, structured practice, or classroom use.

A set of twenty exam-style questions designed to mirror the format and expectations of OCR GCSE Computer Science assessments for J277/02. This resource covers two closely linked topics that students regularly lose marks on - testing and maintainability, with questions that reflect exactly how OCR assesses them: identifying and correcting logic errors in pseudocode, completing test plans, classifying test data, and applying maintainability techniques to given code. Included: 20 carefully structured questions covering errors, test data types, iterative and final testing, comments, naming conventions, subprograms, and more Full answers with mark allocations, written for students not teachers Watch out boxes targeting the specific misconceptions flagged in OCR examiner reports Stretch & challenge questions to push deeper understanding without going beyond the spec OCR-style pseudocode throughout, so students see exactly what they’ll face in the exam A practical, ready-to-use resource to support effective exam preparation and reduce marking workload.

20 exam-style questions on the CPU for OCR GCSE Computer Science (J277/01), with full answers and guidance — free to download. Covers CPU components and registers (ALU, CU, MAR, MDR, PC, accumulator), the fetch-execute cycle, and CPU performance characteristics (clock speed, number of cores, cache size), with questions modelled on the style and command words used in actual J277 papers: complete the table, identify the error, describe, explain, evaluate, and a scenario-based justify question worth 4 marks. Includes: 40 marks across 20 questions, split into three progressive sections Scenario questions with data tables, matching the real exam format Answers written for students, not teachers — no “award 1 mark” language Watch out boxes targeting the specific misconceptions flagged in OCR examiner reports Stretch & challenge questions to deepen understanding without going beyond the spec This is the first resource in a growing series covering the full J277 specification. If it works for your students, the same format and quality is available across other key topics including Storage, Network Security, Input Validation, and Operating Systems.