IB ESS Paper 1 is a case-study-based exam worth 25% of your final grade at SL and 30% at HL. The entire paper revolves around one detailed case study — there are no separate sections.
A strong exam strategy can make the difference between average and excellent results. Here is how to approach the paper with confidence.
Paper 1 format overview
ESS Paper 1 is built around a single case study. You receive a resource booklet containing the case study material, and all questions are based on it.
- SL: 1 hour, 35 marks
- HL: 2 hours, 70 marks
Questions progress from short-answer to more extended responses, all linked to the case study. A calculator is required.
Time management
Use the 2-minutes-per-mark rule to pace yourself through the paper:
- Short-answer questions (1–3 marks): 2–6 minutes each
- Extended-response questions (4–7 marks): 8–14 minutes each
- Review: Save 5 minutes at the end to check your answers
How to tackle the case study
Since every question relates to the case study, how you read it determines your success:
For targeted Paper 1 practice with detailed marking feedback, check out our Past Paper Feedback tool.
- Spend 5–10 minutes reading the case study thoroughly before answering any questions
- Underline key data, figures, and environmental terms
- Reference specific data from the case study in your answers — this shows application and scores higher
- Match your answer depth to the marks available: 1-mark questions need one clear point
Extended-response strategy
The later questions in the paper require longer, more structured responses. Focus on:
- Connecting your ESS knowledge directly to the case study material
- Using specific data or examples from the text provided
- Planning your answer briefly before writing
For the highest-value 9-mark questions (found in Paper 2), see our guide on structuring 9-mark ESS answers for the full framework.
Common mistakes
- Not referencing the case study: Your answers must use the provided material — generic textbook answers score lower
- Running out of time: Spending too long on low-mark questions
- Skipping the plan: A 30-second plan leads to a much better-structured response for higher-mark questions
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