COMPUTER-SCIENCE-J277 · Cambridge OCR GCSE (9–1)
COMPUTER-SCIENCE-J277/11
Computer Systems
Computer Science · June 2022 · Variant 1
Relative difficulty
Analysis source: OCR
Analysis aligned to the official syllabus and assessment design.
3.2 / 5
160
180 min
Designing, creating and refining algorithms
Cohort performance
Session statistics from official examination reports
Total marks
160
Duration
180 min
Session difficulty
3.2 / 5
Key examiner messages
Top priorities from the principal examiner before you revise
The 2022 J277 assessment is rated as a 3.2 out of 5 (Medium).
While the mathematical conversions and theory aspects were generally accessible, Paper 2 presented a rigorous test of algorithmic design.
Many candidates found the multi-criteria validation coding and loop design highly challenging under exam conditions.
Question difficulty map
How candidates performed on each question in this series
No data available in official reports
Assessment objectives
Skill and AO weighting from official examiner commentary
Skill weighting
Shows the skill mix this paper tested most heavily.
Algorithmic Design
Weight: 8100%Systems &
Weight: 675%Networking Mathematical
Weight: 563%Critical Evaluation
Weight: 338%Database & SQL Querying
Weight: 113%
Method marks watchlist
Where working, steps, or method marks were commonly lost
No data available in official reports
Recurring mistakes across years
Themes examiners flag in multiple recent sessions for this subject
No data available in official reports
Question choice intelligence
Mean scores and popularity for optional questions (HKDSE electives)
No data available in official reports
Level exemplars
What candidate scripts at each grade level looked like
No data available in official reports
Grade & admission context
How marks relate to grade thresholds and entry standards
Report type
Examiner report — national grade boundaries and question-level commentary
Level 9
Approx. 83% of maximum mark
Level 8
Approx. 74% of maximum mark
Level 7
Approx. 66% of maximum mark
Level 6
Approx. 56% of maximum mark
Level 5
Approx. 47% of maximum mark
Level 4
Approx. 38% of maximum mark
Level 3
Approx. 28% of maximum mark
Level 2
Approx. 19% of maximum mark
Deep insights
What top candidates did
Techniques and approaches examiners rewarded in this series
No data available in official reports
Command word playbook
How to match each command word to the expected response style
Name or point to the specific feature asked for — avoid extra explanation.
Give reasons and link mechanism to outcome; each point needs a because/so chain.
State features in sequence or list observable properties — do not explain causes unless asked.
Match the expected response style for “State” questions.
Present multiple perspectives with evidence; balance breadth and depth.
Match the expected response style for “Complete” questions.
Match the expected response style for “Write” questions.
Time traps
Sections where candidates spent disproportionate time relative to marks
Min per mark: 1.1
Syllabus traceability
Topics linked to questions and mark weighting in this session
Designing, creating and refining algorithms
25 marks this session
Data storage
18 marks this session
Wired and wireless networks, protocols and layers
18 marks this session
MCQ trap analytics
Commonly chosen wrong options from examiner commentary
No data available in official reports
Topic heatmap across years
Mark concentration by topic and exam year for this subject
Mark intensity
Data storage
Designing, creating and refining algorithms
Wired and wireless networks, protocols and layers
Additional programming techniques
Ethical, legal, cultural and environmental impact
Defensive design
Difficulty trend
How session difficulty has shifted across recent years
Paper comparison
Marks and duration breakdown across papers in this session
J277/01 Computer Systems: J277/02 Computational thinking, algorithms and programming:
Marks you can still earn
Where valid approaches outside the mark scheme may still gain credit
No data available in official reports
Practise what examiners flagged
Target weak topics from this report inside the Revui app
Designing, creating and refining algorithms
25 marks this session
Practise in RevuiData storage
18 marks this session
Practise in RevuiWired and wireless networks, protocols and layers
18 marks this session
Practise in RevuiSelf-diagnostic checklist
Key actions before you sit this paper — copy and tick off as you revise
- 1Message
The 2022 J277 assessment is rated as a 3.2 out of 5 (Medium).
- 2Message
While the mathematical conversions and theory aspects were generally accessible, Paper 2 presented a rigorous test of algorithmic design.
- 3Message
Many candidates found the multi-criteria validation coding and loop design highly challenging under exam conditions.
Teacher briefing pack
One-page session summary for tutors and classroom review
June 2022 2022
Computer Science
The 2022 J277 assessment is rated as a 3.2 out of 5 (Medium). While the mathematical conversions and theory aspects were generally accessible, Paper 2 presented a rigorous test of algorithmic design. Many candidates found the multi-criteria validation coding and loop design highl
The 2022 J277 assessment is rated as a 3.2 out of 5 (Medium).
While the mathematical conversions and theory aspects were generally accessible, Paper 2 presented a rigorous test of algorithmic design.
Many candidates found the multi-criteria validation coding and loop design highly challenging under exam conditions.
- Total marks
- 160
- Duration
- 180 min
- Session difficulty
- 3.2 / 5
Session analysis
The 2022 J277 assessment is rated as a 3.2 out of 5 (Medium). While the mathematical conversions and theory aspects were generally accessible, Paper 2 presented a rigorous test of algorithmic design. Many candidates found the multi-criteria validation coding and loop design highly challenging under exam conditions.
Updated Jun 14, 2026
Paper breakdown
J277/01 Computer Systems: J277/02 Computational thinking, algorithms and programming:
Top chapters
Exam structure insights
Marks by chapter
See where the marks were concentrated so revision time goes to the highest-value topics.
Mark accessibility
Estimate which marks were basic, mid-level, or high-difficulty.
81% within easy or medium reach
Command word frequency
Spot common command words so answers match the expected response style.
Question type mix
Compare the mark share of each paper section and question type.
Mathematical, Logical & Practical Tasks
56·15·35%
Short Answer & Explanations
48·24·30%
Coding & Algorithmic Design
29·6·18%
Multiple Choice & Grids
19·5·12%
Long Essay Discussion
8·1·5%
Study ROI
Bigger bubbles recur more often; higher bubbles carry more marks, helping you rank revision priorities.
Time vs marks
Compare marks with suggested time allocation to plan exam pacing.
Paper 1: Computer S…
0.89 m/minTotal marks
80
Total time
90 min
Avg pace
0.89
Next-year prediction
Topics worth watching next year, with the reason shown directly below each bar.
Operating systems (Systems software)
90%90%
Embedded systems (Systems architecture)
85%85%
Threats to computer systems and networks
80%80%
Difficulty Verdict
The 2022 J277 assessment is rated as a 3.2 out of 5 (Medium). While the mathematical conversions and theory aspects were generally accessible, Paper 2 presented a rigorous test of algorithmic design. Many candidates found the multi-criteria validation coding and loop design highly challenging under exam conditions.
Where the Marks Are
The marks are heavily concentrated in Designing, creating and refining algorithms (25 marks), Data storage (18 marks), and Wired and wireless networks (18 marks). Securing top marks required demonstrating a deep understanding of standard search/sort routines alongside the ability to construct complete structured algorithms from scratch.
Examiner notes & key calculations
- Analog to Digital Conversion: Students struggled to explain sound sampling with sufficient technical precision. A common error was failing to state that the amplitude of the analogue wave is measured at regular, specific intervals and stored sequentially as binary numbers.
- Contention vs. Bandwidth: In network performance, many wrote that adding devices 'decreases bandwidth' rather than explaining that it divides the available bandwidth or increases data collisions.
- Flowchart Notation: Candidates frequently lost marks by using incorrect flowchart shapes (e.g., using rectangles instead of parallelograms for inputs and outputs, or omitting decision exit labels 'Yes'/'No').
- SQL Syntax: Common syntax errors included writing 'IF' instead of the standard 'WHERE' clause, or using 'SELECT ALL' instead of 'SELECT *'.
Exam tips
Paper format
- Duration
- 1h 30min
- Total marks
- 80
- Weighting
- 50%
- Question types
- Short Answer & Conversions, Structured Explanations & Diagrams, Quality of Extended Response Essay
Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.