OCR GCSE Computer Science scheme of work
A free two-year OCR GCSE Computer Science (J277) scheme of work, unit by unit. Each unit lists its lessons, what pupils should be able to do by the end, key vocabulary, curriculum links and assessment, with a direct link to the matching Teach io learn guide.
Two-year overview
Paper 1 units in blue, Paper 2 in purple.
Year 10
Practical programming should run every week from Year 10, not just in the programming unit. Year 11 spring and summer are left for applying knowledge, mock exams and revision. Timings assume around three lessons a week.
National curriculum, RSHE and careers links
J277 1.1 · J277 2.2 · J277 1.2 · J277 2.5 · J277 1.3 · J277 1.4 · J277 1.5
Online risks, personal data and privacy are reinforced in these units. The full RSHE 2025 mapping is in the online safety lessons.
Every unit names jobs it leads to, so teachers can link curriculum learning to careers in each topic.
All units
At KS4 the exam specification is the main reference. The national curriculum statements are summarised from the KS4 Computing programme of study.
Units in teaching order
Systems Architecture
What the CPU is for and how it works. Pupils meet the ALU, control unit, cache and registers, follow the fetch-execute cycle through the von Neumann registers, explain what makes one CPU faster than another, and recognise embedded systems in everyday devices.
Lessons
- The purpose of the CPU
- CPU components
- Von Neumann architecture
- The fetch-decode-execute cycle
- CPU performance
- Embedded systems
- Bringing it together
By the end, pupils can
- State the purpose of the CPU and outline the fetch-decode-execute cycle.
- Describe the function of the ALU, control unit, cache and registers.
- Explain the stored program concept at the heart of the von Neumann architecture.
- Identify what the PC, MAR, MDR and accumulator each hold.
- Describe the fetch stage of the fetch-execute cycle, naming a register in every step.
Key vocabulary
Curriculum links
- NC KS4 AKnowledge and creativity in computer science
- CareersHardware engineer, embedded systems developer
Assessment: end-of-guide assessment (80% to pass each step), plus a 6-mark CPU performance question and a 4-mark fetch stage question.
Programming Fundamentals
The building blocks pupils use in every Paper 2 answer and every programming task. Taught as a block early in Year 10, then practised weekly in Python and OCR Exam Reference Language so that it is secure by the time pupils meet algorithms and robust programs.
Lessons
- Variables, constants, input and output
- Operators
- Data types and casting
- Sequence and selection
- Iteration
- String manipulation
- Arrays
- File handling
- Records and SQL
- Sub programs and random numbers
- Bringing it together
By the end, pupils can
- Use variables, constants, inputs, outputs and assignment.
- Use arithmetic operators including MOD, DIV and exponentiation, comparison operators and the Boolean operators AND, OR and NOT.
- Choose suitable data types (integer, real, Boolean, character, string) and cast between them.
- Use sequence, selection (if, elseif, else, nested if, switch/case) and iteration (for, while, do…until).
- Manipulate strings using length, substring, left, right, upper, lower, ASC and CHR.
Key vocabulary
Curriculum links
- NC KS4 AKnowledge and creativity in computer science
- NC KS4 BProblem-solving, design and computational thinking
- CareersSoftware developer, games programmer
Assessment: end-of-guide assessment, plus short coding tasks each week in Python and Exam Reference Language.
Memory and Storage
How computers hold data, from RAM and ROM to hard drives, SSDs and discs, and how everything is stored in binary. Pupils convert between number bases, add and shift binary, explain ASCII and Unicode, calculate image and sound file sizes and choose between lossy and lossless compression.
Lessons
- Primary storage
- Secondary storage
- Units of data storage
- Binary, denary and hexadecimal
- Binary addition and binary shifts
- Characters
- Images and sound
- Compression
- Bringing it together
By the end, pupils can
- Explain why computers need primary storage and compare RAM and ROM.
- Describe why virtual memory may be needed and how it works.
- Compare magnetic, optical and solid state storage and recommend a device for a scenario.
- Convert between data units from bit to petabyte and calculate storage requirements.
- Convert between binary, denary and hexadecimal, add binary numbers and carry out binary shifts.
Key vocabulary
Curriculum links
- NC KS4 AKnowledge and creativity in computer science
- CareersData engineer, digital media technician
Assessment: end-of-guide assessment, a 6-mark storage discussion and calculation questions. Feeds the Autumn 2 checkpoint.
Algorithms
Thinking like a programmer before writing code. Pupils use abstraction and decomposition, plan with structure diagrams, write and read Exam Reference Language and flowcharts, find errors with trace tables, and carry out the searching and sorting algorithms OCR names.
Lessons
- Computational thinking
- Inputs, processes, outputs and structure diagrams
- Pseudocode and flowcharts
- Common errors and trace tables
- Searching algorithms
- Bubble sort and insertion sort
- Merge sort and comparing algorithms
- Bringing it together
By the end, pupils can
- Explain abstraction, decomposition and algorithmic thinking and apply them to a problem.
- Identify the inputs, processes and outputs of a problem and draw a structure diagram.
- Write and interpret algorithms in OCR Exam Reference Language using sequence, selection, iteration and nesting.
- Read and draw flowcharts using the six OCR flowchart symbols.
- Identify syntax and logic errors, suggest fixes and refine an algorithm.
Key vocabulary
Curriculum links
- NC KS4 BProblem-solving, design and computational thinking
- CareersSoftware engineer, data scientist
Assessment: end-of-guide assessment and a 6-mark searching question; pupils must show every stage of a sort.
Boolean Logic
AND, OR and NOT as gates, expressions and truth tables. Pupils draw and read logic diagrams with more than one gate, build truth tables for up to three inputs and turn real-life situations, like an alarm or a vending machine, into logic.
Lessons
- Logic gates
- Truth tables
- Combining Boolean operators
- Logic diagrams
- Solving problems with truth tables
- Bringing it together
By the end, pupils can
- State what a Boolean value is and describe what a logic gate does.
- Recognise the AND, OR and NOT gate symbols and describe the output of each gate.
- Write the truth tables for AND, OR and NOT and work out how many rows a truth table needs.
- Combine AND, OR and NOT in Boolean expressions, using brackets correctly.
- Complete truth tables for combined expressions with up to three inputs, using working columns.
Key vocabulary
Curriculum links
- NC KS4 BProblem-solving, design and computational thinking
- CareersElectronics engineer, chip designer
Assessment: end-of-guide assessment and a 6-mark logic scenario with a three-input truth table.
Programming Languages and IDEs
Why code has to be translated and the tools programmers use. Pupils compare high- and low-level languages, explain how compilers and interpreters differ and when to choose each, and describe how an IDE helps them write and debug programs.
Lessons
- High-level and low-level languages
- Translators
- Compilers and interpreters
- The Integrated Development Environment (IDE)
- Bringing it together
By the end, pupils can
- Describe the characteristics and purpose of high-level and low-level languages.
- Explain the differences between high-level and low-level languages and when each is used.
- Identify machine code and assembly language as the two types of low-level language.
- Explain why translators are needed to convert source code into machine code.
- Describe how a compiler and an interpreter translate a program.
Key vocabulary
Curriculum links
- NC KS4 AKnowledge and creativity in computer science
- NC KS4 BProblem-solving, design and computational thinking
- CareersSoftware developer, games programmer
Assessment: end-of-guide assessment and a 6-mark compiler versus interpreter question.
Networks, Connections and Protocols
How devices connect, from a school LAN to the internet. Pupils compare network types and hardware, explain how DNS and the cloud work, draw star and mesh topologies, and describe IP and MAC addressing, common protocols and why networks use layers.
Lessons
- LANs, WANs and network performance
- Client-server and peer-to-peer networks
- Network hardware
- The Internet
- Star and mesh topologies
- Wired and wireless connections
- IP and MAC addressing
- Standards, protocols and layers
- Bringing it together
By the end, pupils can
- Describe the difference between a LAN and a WAN and explain how bandwidth and the number of devices affect network performance.
- Compare client-server and peer-to-peer networks and recommend one for a given scenario.
- Describe the purpose of a NIC, switch, router and wireless access point, and compare transmission media.
- Explain how DNS converts a URL into an IP address and describe hosting, the cloud, web servers and clients.
- Draw star and mesh topologies and explain the advantages and disadvantages of each.
Key vocabulary
Curriculum links
- NC KS4 AKnowledge and creativity in computer science
- CareersNetwork engineer, cloud engineer
Assessment: end-of-guide assessment and a 6-mark network recommendation question.
Network Security
The threats a network faces and how to stop them. Pupils learn how malware, phishing, brute-force and denial of service attacks, interception and SQL injection work, then match each one to a defence such as firewalls, encryption, access levels or penetration testing.
Lessons
- Malware
- Social engineering
- Brute-force and denial of service attacks
- Data interception and SQL injection
- Penetration testing, anti-malware and firewalls
- Access levels, passwords, encryption and physical security
- Bringing it together
By the end, pupils can
- Describe what malware is, how it gets onto a system and the harm it can cause.
- Explain how social engineering, including phishing, exploits people as the weak point in a system.
- Describe how brute-force and denial of service attacks are carried out and their purpose.
- Explain how data can be intercepted or stolen and how SQL injection attacks a database.
- Describe how penetration testing, anti-malware software and firewalls identify and limit threats.
Key vocabulary
Curriculum links
- NC KS4 AKnowledge and creativity in computer science
- NC KS4 CHow technology affects safety, privacy and identity
- RSHEOnline and media: online risks, scams and protecting personal information
- CareersCyber security analyst, penetration tester
Assessment: end-of-guide assessment and a 6-mark threats and prevention question. Covered in the Year 10 exam.
Systems Software
What the operating system does behind the scenes and the utilities that keep a computer running well. Pupils cover the five OS functions, from the user interface to file management, and the purpose of encryption, defragmentation and compression software.
Lessons
- The operating system and the user interface
- Memory management and multitasking
- Peripheral management and drivers
- User management and file management
- Utility software and encryption
- Defragmentation and data compression
- Bringing it together
By the end, pupils can
- State the purpose of an operating system and name its five functions.
- Describe the features of a user interface and compare a GUI with a command-line interface.
- Explain how memory management allocates RAM and allows multitasking.
- Describe how the operating system manages peripherals and why device drivers are needed.
- Describe how user management and access rights keep data secure, and what file management does.
Key vocabulary
Curriculum links
- NC KS4 AKnowledge and creativity in computer science
- CareersIT support technician, systems administrator
Assessment: end-of-guide assessment and a 6-mark school computers scenario.
Producing Robust Programs
Writing code that does not break. Pupils plan for misuse, write validation and login routines, make code easy to maintain, and test programs with normal, boundary, invalid and erroneous data before refining them.
Lessons
- Anticipating misuse
- Input validation
- Authentication
- Maintainability
- Testing and types of error
- Test data and refining algorithms
- Bringing it together
By the end, pupils can
- Explain what defensive design is and why programs must anticipate accidental and deliberate misuse.
- Describe range, type, length, presence and format checks and write a validation loop in OCR Exam Reference Language.
- Explain how authentication confirms a user’s identity and write a simple username and password check.
- Explain how sub programs, naming conventions, indentation and commenting improve maintainability.
- Compare iterative and final testing and state the purpose of testing.
Key vocabulary
Curriculum links
- NC KS4 BProblem-solving, design and computational thinking
- CareersSoftware tester, app developer
Assessment: end-of-guide assessment, a written validation algorithm and a test plan task.
Ethical, Legal, Cultural and Environmental Impacts
The wider effects of technology on people and the planet. Pupils weigh up automation, AI, the digital divide, e-waste and privacy, apply the Data Protection Act, Computer Misuse Act and copyright law to scenarios, and compare open source and proprietary licences.
Lessons
- Ethical and legal issues
- Cultural issues
- Environmental issues
- Privacy issues
- Data protection and computer misuse
- Copyright and software licences
- Bringing it together
By the end, pupils can
- Explain the difference between ethical and legal issues and identify the stakeholders affected by a technology.
- Discuss cultural impacts of digital technology, including the causes and effects of the digital divide.
- Describe the negative and positive environmental impacts of digital technology, including e-waste and energy use.
- Explain privacy issues caused by the collection of personal data and by surveillance.
- State the purpose of the Data Protection Act 2018 and apply its principles to scenarios.
Key vocabulary
Curriculum links
- NC KS4 CHow technology affects safety, privacy and identity
- RSHEOnline and media: personal data, privacy and rights online
- CareersData protection officer, technology law and policy
Assessment: end-of-guide assessment and a 6-mark smart CCTV discussion. Covered in the Year 11 mocks.
Frequently asked questions
Is this OCR GCSE Computer Science scheme of work free to use?
Yes. The scheme of work, unit plans and lesson lists are free for any teacher to use and adapt. Pupils need a Teach io Student, Teacher or School plan to open the full learn guides and assessments; the first lesson of every guide is a free sample.
Which OCR specification does it follow?
It follows the OCR GCSE Computer Science specification (J277). Every unit is labelled with its specification reference and the paper it is assessed in.
How long does the course take to teach?
The plan spreads the theory across Year 10 and the first term of Year 11, assuming around three Computer Science lessons a week, leaving Year 11 spring and summer for applying knowledge, mock exams and revision. Adjust the timings to your timetable.
How are pupils assessed?
Each learn guide ends with an assessment. Pupils need 80% on a step to move on, and every question gives feedback on the misconception behind a wrong answer. Teachers see results by class so they know what to reteach before the exams.
Does it map to the national curriculum?
Yes. Each unit shows which KS4 Computing national curriculum statements it covers, any RSHE links and the careers it leads to, so you can evidence coverage and Gatsby Benchmark 4.
More schemes of work
Use this scheme with your department
Teacher and School plans give every pupil the learn guides and assessments above, with results by class so you can see which units need reteaching.