Pearson Edexcel GCSE Computer Science Paper 1 2025 M S

Download the official Pearson Edexcel GCSE Computer Science (9–1) Paper 1: Principles of Computer Science mark scheme for the Summer 2025 examination series (1CP2/01). This examiner-approved PDF contains complete answers, indicative content, mark allocations, trace-table solutions, algorithm explanations, level descriptors, and official Pearson marking guidance used during the June 2025 GCSE Computer Science examinations.

The mark scheme provides full examiner guidance for all sections of the Paper 1 examination, including binary and hexadecimal representation, data storage, sound compression, embedded systems, programming languages, cybersecurity, networking, Boolean logic, search and sorting algorithms, trace tables, and computational thinking.

Students can study exactly how Pearson Edexcel examiners award marks for binary conversion, hexadecimal notation, binary shifts, sound compression calculations, Boolean logic tables, networking protocols, pseudocode analysis, and algorithm-tracing questions. The document includes accepted alternative answers, linked-explanation guidance, and detailed examiner instructions for awarding marks consistently across different response styles.

Question 1 covers data representation and storage concepts including gibibytes, binary powers, hexadecimal characteristics, hexadecimal advantages, lossy sound compression, binary shifts, and binary-to-hexadecimal conversion. The mark scheme explains why hexadecimal uses digits 0–9 and letters A–F, how memory addresses are represented efficiently, and why lossy compression improves streaming and reduces storage usage.

Question 2 focuses on computer systems, embedded systems, storage technologies, translators, assembly language, virtual memory, and file recovery. Students can review official examiner guidance for interpreter characteristics, assembly-language features, audit trails, paging and swapping processes, and embedded-system functions in washing machines such as controlling spin speed, timers, water temperature, and load monitoring.

Question 3 examines cybersecurity, open-source software, malware, acceptable-use policies, and data protection principles. The mark scheme contains official GDPR-related answers involving consent, secure data storage, data retention, third-party sharing restrictions, and users’ rights to access or remove their personal data. It also includes explanations of viruses, trojans, keyloggers, and safe-computing practices.

Question 4 explores networking concepts including WANs, TCP, FTP, HTTP/HTTPS, Wi-Fi, Bluetooth, Zigbee, ethical hacking, penetration testing, wired and wireless media, and network topologies. The mark scheme provides extensive indicative content for evaluating bus, star, and mesh topologies alongside Ethernet and wireless networking advantages and disadvantages. Pearson’s level descriptors explain how students achieve higher-band marks in 6-mark evaluative networking questions.

Question 5 contains detailed answers for Boolean logic expressions, truth tables, trace tables, record traversal, pseudocode corrections, linear-search worst-case analysis, bubble-sort best-case analysis, and binary-search midpoint calculations. Students can study complete worked solutions for trace tables and binary-search algorithms using both rounding-down and rounding-up midpoint methods.

The document also includes Pearson’s official general marking guidance explaining positive marking, acceptable equivalent answers, linked-marking principles, alternative responses, and level-based assessment criteria used by examiners during GCSE Computer Science marking.

Ideal for revision, self-assessment, mock exam marking, classroom feedback, intervention sessions, programming practice, algorithm analysis, and preparation for future GCSE Computer Science exams, this downloadable PDF provides authentic examiner guidance and realistic examples of high-scoring Edexcel Computer Science responses.

This document is designed for Year 10 and Year 11 students studying Pearson Edexcel GCSE Computer Science (9–1), including students preparing for the 2026 examinations, independent learners, home-educated candidates, private candidates, and learners aiming for grades 7–9 in GCSE Computer Science.

It is also highly valuable for Computer Science teachers, tutors, coding clubs, revision centres, intervention coordinators, and parents who require authentic examiner guidance, algorithm solutions, networking evaluation criteria, and official Pearson assessment standards for GCSE Computer Science revision.