A-Level Computer Science Essay Questions: 9618 has no essay questions. How to write "extended responses" in the theory papers.

First, a clarification: Cambridge A-Level Computer Science (9618) has no essay paper or essay questions; Edexcel IAL does not offer Computer Science. However, the two theory papers—AS Paper 1 and A Level Paper 3—explicitly state in the syllabus that questions require "some short answers and some longer answers." These longer answers are the closest thing to "essays" in Computer Science: explaining principles, comparing solutions, and justifying choices. We mentioned in How A-Level Computer Science is Tested that "terminology and definitions must be accurate." This article focuses specifically on the longer answers in the theory papers: what the syllabus assessment objectives mean, what the command words mean, and how to write them. This is based on the Cambridge 9618 syllabus (2027–2029). For programming questions, see article 193; for theory content, see articles 218 and 233.

I. Where to Find the Longer Answers

• Paper 1: Theory Fundamentals (AS): Covers Chapters 1–8. Questions require some short and some longer answers, testing knowledge and understanding of Computer Science principles and the application of these principles to solve problems;
• Paper 3: Advanced Theory (A Level): Covers Chapters 13–20, also requiring both short and longer answers;
• Paper 2: Problem-solving and Programming (AS): Also includes longer answers, but these test programming knowledge and skills, requiring answers in pseudocode (see article 193);
• Calculators are not allowed in any of the papers.

II. What the Assessment Objectives Tell Us

The takeaway from this table is straightforward: the two theory papers are 60% knowledge and understanding, and 40% application, with no AO3. In other words, scoring well on the longer answers in the theory papers relies on accurate explanations of principles and applying those principles to the contexts given in the questions, rather than writing lengthy evaluations like in humanities essays.

III. Command Words

Command words and their meanings listed in the syllabus (excerpted for those relevant to longer answers in the theory papers):

The syllabus also lists other command words such as Analyse, Calculate, Complete (complete a diagram or table), Consider, Define, Demonstrate, Develop, Draw (in this course, this means "draw lines to match terms with descriptions"), Examine, Give, Identify, and Sketch.

IV. Which Syllabus Topics Are Suitable for Longer Answers

The syllabus learning outcomes use phrasing like "Show understanding of," "Explain," and "Justify." These types of requirements typically call for longer answers (based on our experience). Here are a few examples from the syllabus text:

• Paper 1: Justify whether to choose a bitmap or vector graphic for a given task; choose lossy or lossless compression for a given scenario and justify the choice; explain the limitations of file storage methods and how relational databases solve them (see article 233);
• Paper 3: Differences between RISC and CISC; advantages, disadvantages, and use cases of circuit switching and packet switching; differences between paging and segmentation; how packet switching transmits messages across a network; advantages and disadvantages of virtual machines; uses, advantages, and disadvantages of quantum cryptography; how neural networks drive machine learning (see article 218).

V. How to Write Them

Here are some practical tips based on our experience:

1. Write points according to the marks: Computer Science mark schemes typically award marks for specific points. Generally, write one clear sentence for each marking point, and prepare as many distinct points as the marks available;
2. Use accurate terminology: Use syllabus terminology such as "time slice," "interrupt," "pipeline," and "referential integrity." Avoid vague, everyday language;
3. For "Explain," write the "why": Don't just write "packet switching is efficient." Also write "because it does not require a dedicated line, allowing multiple communications to share the link";
4. For "Compare," write in pairs: Address both sides in every point, for example, "RISC has a fixed instruction length, whereas CISC has a variable instruction length." Do not split them into separate paragraphs;
5. For "Justify," tie it back to the context: "This task should use vector graphics because the image needs to be scaled without distortion and consists of simple geometric shapes." The justification must be relevant to the context given in the question;
6. For application questions, read the context first: AO2 accounts for 40% of the marks. Questions often provide a scenario (e.g., a company's network, a piece of code, a table). Your answer must use the information from the scenario;
7. Use diagrams to help: Logic circuits, E-R diagrams, protocol stacks, and process state diagrams. Draw them when appropriate, as they are often clearer than text.

VI. Common Reasons for Losing Marks

Here is a summary based on our experience:

• Repeating points by rephrasing the same idea;
• Writing only the conclusion without the reason;
• Only writing about one side in comparison questions;
• Giving reasons that are detached from the context, resulting in vague statements that apply to any situation;
• Using inaccurate terminology or failing to align Chinese and English concepts (since the exam is in English, terminology must be mastered in English).

Final Thoughts

Computer Science has no essay questions, but the theory papers do have "longer answers." The syllabus weightings show that these answers rely on accurate principles and application to the context, rather than lengthy evaluations. By preparing points according to the marks, using accurate terminology, writing the "why" for Explain, writing in pairs for Compare, and tying Justify back to the context, you can consistently score well on the longer answers in the theory papers. If you need A-Level Computer Science tutoring, feel free to chat with our teachers.

Verification note: This article was verified in September 2026. The statements that 9618 papers "require some short and some longer answers," the scope of each paper, the prohibition of calculators, the assessment objective weightings for each paper, the list of command words and their meanings, and the learning outcomes cited in Part IV are all from the Cambridge International Computer Science 9618 syllabus for 2027, 2028 and 2029. The meanings of the three assessment objectives and the fact that Edexcel does not offer Computer Science were verified in article 170 on this site. The topics suitable for longer answers, answering techniques, and common reasons for losing marks are our practical recommendations based on experience.

References:

• Cambridge International: Computer Science 9618 Syllabus 2027–2029 (PDF)