COMPUTER-SCIENCE-1CP2 · Pearson Edexcel GCSE (9–1)
COMPUTER-SCIENCE-1CP2/21
Paper 2
Computer Science · June 2023 · Variant 1
Relative difficulty
Analysis source: Pearson Edexcel
Analysis aligned to the official syllabus and assessment design.
4.5 / 5
150
210 min
Practical code authoring, variable manipulation, and subprogram creation (Develop Code)
Cohort performance
Session statistics from official examination reports
Total marks
150
Duration
210 min
Session difficulty
4.5 / 5
Key examiner messages
Top priorities from the principal examiner before you revise
In Paper 1, accessible marks were concentrated in the data representation conversions (denary to hexadecimal, bits calculation) and foundational network concepts.
On the other hand, high-tariff questions like the 6-mark Sound Representation Graph (Question 5f) and the 6-mark Decomposition/Abstraction discussion (Question 4f) required precise structure to secure full credit.
In Paper 2, the initial 15 marks across Question 1 and 2 (code identification and basic syntax fixes) were highly accessible, whereas the 15-mark programming tasks (Questions 4, 5, and 6) tested robust logic, including defensive programming, array searches, and advanced string manipulation.
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.
Practical
Weight: 6100%Logic &
Weight: 583%Algorithmic Theoretical
Weight: 467%Recall
Weight: 233%Mathematical
Weight: 117%
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. 85% of maximum mark
Level 8
Approx. 75% of maximum mark
Level 7
Approx. 65% of maximum mark
Level 6
Approx. 53% of maximum mark
Level 5
Approx. 43% of maximum mark
Level 4
Approx. 32% of maximum mark
Level 3
Approx. 23% of maximum mark
Level 2
Approx. 13% 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.
State features in sequence or list observable properties — do not explain causes unless asked.
Give reasons and link mechanism to outcome; each point needs a because/so chain.
Match the expected response style for “Amend” questions.
Present multiple perspectives with evidence; balance breadth and depth.
Match the expected response style for “Write” questions.
Time traps
Sections where candidates spent disproportionate time relative to marks
Min per mark: 1.7
Min per mark: 1.7
Min per mark: 1.5
Min per mark: 1.3
Syllabus traceability
Topics linked to questions and mark weighting in this session
Develop code
62 marks this session
Data types and structures
17 marks this session
Data representation
12 marks this session
Algorithms
10 marks this session
Networks
10 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
Develop code
Algorithms
Networks
Data types and structures
Data representation
Binary
Difficulty trend
How session difficulty has shifted across recent years
Paper comparison
Marks and duration breakdown across papers in this session
Paper 1: Principles of Computer Science:
Paper 2: Application of Computational Thinking:
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
Develop code
62 marks this session
Practise in RevuiData types and structures
17 marks this session
Practise in RevuiData representation
12 marks this session
Practise in RevuiAlgorithms
10 marks this session
Practise in RevuiNetworks
10 marks this session
Practise in RevuiSelf-diagnostic checklist
Key actions before you sit this paper — copy and tick off as you revise
- 1Message
In Paper 1, accessible marks were concentrated in the data representation conversions (denary to hexadecimal, bits calculation) and foundational network concepts.
- 2Message
On the other hand, high-tariff questions like the 6-mark Sound Representation Graph (Question 5f) and the 6-mark Decomposition/Abstraction discussion (Question 4f) required precise structure to secure full credit.
- 3Message
In Paper 2, the initial 15 marks across Question 1 and 2 (code identification and basic syntax fixes) were highly accessible, whereas the 15-mark programming tasks (Questions 4, 5, and 6) tested robust logic, including defensive programming, array searches, and advanced string manipulation.
Teacher briefing pack
One-page session summary for tutors and classroom review
June 2023 2023
Computer Science
In Paper 1, accessible marks were concentrated in the data representation conversions (denary to hexadecimal, bits calculation) and foundational network concepts. On the other hand, high-tariff questions like the 6-mark Sound Representation Graph (Question 5f) and the 6-mark Deco
In Paper 1, accessible marks were concentrated in the data representation conversions (denary to hexadecimal, bits calculation) and foundational network concepts.
On the other hand, high-tariff questions like the 6-mark Sound Representation Graph (Question 5f) and the 6-mark Decomposition/Abstraction discussion (Question 4f) required precise structure to secure full credit.
In Paper 2, the initial 15 marks across Question 1 and 2 (code identification and basic syntax fixes) were highly accessible, whereas the 15-mark programming tasks (Questions 4, 5, and 6) tested robust logic, including defensive programming, array searches, and advanced string manipulation.
- Total marks
- 150
- Duration
- 210 min
- Session difficulty
- 4.5 / 5
Session analysis
In Paper 1, accessible marks were concentrated in the data representation conversions (denary to hexadecimal, bits calculation) and foundational network concepts. On the other hand, high-tariff questions like the 6-mark Sound Representation Graph (Question 5f) and the 6-mark Decomposition/Abstraction discussion (Question 4f) required precise structure to secure full credit. In Paper 2, the initial 15 marks across Question 1 and 2 (code identification and basic syntax fixes) were highly accessible, whereas the 15-mark programming tasks (Questions 4, 5, and 6) tested robust logic, including defensive programming, array searches, and advanced string manipulation.
Updated Jun 14, 2026
Paper breakdown
Paper 1: Principles of Computer Science:
Paper 2: Application of Computational Thinking:
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.
73% 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.
Practical Coding: Unstructured Authoring
(P2)
64·3·43%
Short Answer / State / Define
35·22·23%
Practical Coding: Completion / Identification
(P2)
30·3·20%
Graphical/Flowchart Completion
10·2·7%
Long Answer Discussion
(Q4f)
6·1·4%
Multiple Choice / Binary Choice
5·5·3%
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: Theoretica…
0.74 m/minPaper 1: Analytical…
0.60 m/minPaper 2: Syntax Fix…
0.67 m/minPaper 2: Structured…
0.60 m/minTotal marks
101
Total time
155 min
Avg pace
0.65
Next-year prediction
Topics worth watching next year, with the reason shown directly below each bar.
Subprograms and Parameter Passing
95%95%
Sort Algorithms (Bubble and Merge Sort)
90%90%
Environmental and Global Green Computing
85%85%
Examiner notes & key calculations
- Sound Wave Graphing: Many candidates failed to correctly plot all 10 samples as separate 'X' characters, or they drew smooth curved lines instead of the distinct step/square waves required for digital representation.
- Data Shift Confusions: Students often struggled to articulate the exact logical difference between arithmetic and logical shifts, missing that arithmetic shifts preserve or duplicate the sign bit.
- ASCII vs Integer Parsing: In Paper 2, Question 5, a prevalent mistake was using the int() cast instead of the ord() function to calculate the sum of characters' ASCII values.
- File Handlers: Omitting file close operations or choosing the wrong write mode (using 'append' instead of 'write only' in Question 3) led to automated grading failures.
Analysis is paraphrased for study purposes. Always verify against the official examiner report and mark scheme.