IB ESS Paper 2 is the largest component of your final grade and focuses on data analysis, experimental design, and application of ESS concepts to unfamiliar contexts.
Many students find Paper 2 more challenging than Paper 1 because it requires scientific thinking and data interpretation, not just content recall.
Paper 2 format overview
Standard Level (SL)
- Section A: Short-answer questions based on common stimulus material — 40 marks (all compulsory)
- Section B: Extended-response questions requiring analysis and evaluation — choose 1 from 2 questions (20 marks)
Total time: 2 hours. Total marks: 60.
Higher Level (HL)
- Section A: Short-answer questions based on common stimulus material — 40 marks (all compulsory)
- Section B: Extended-response questions requiring analysis and evaluation — choose 2 from 3 questions (20 marks each, 40 marks total)
Total time: 2 hours 30 minutes. Total marks: 80.
How to analyse data
When presented with graphs, tables, or datasets:
- Identify the variables and their units
- Describe the overall trend or pattern
- Quote specific data points to support your description
- Explain the underlying environmental process that causes the pattern
Practise your Paper 2 responses and see exactly how they would score — try our IB Past Paper Feedback tool.
Linking data to ESS concepts
Paper 2 tests whether you can connect unfamiliar data to ESS knowledge. When answering:
- Name the relevant ESS concept or model
- Explain how the data supports or contradicts the concept
- Consider limitations of the data (sample size, methodology, timeframe)
Structuring your response
For extended-response questions in Section B:
- Start with a clear thesis that addresses the question
- Use evidence from the provided data and your ESS knowledge
- Include evaluation: discuss strengths and limitations of the approach
- End with a reasoned conclusion
Common mistakes
- Describing data without explaining it: Always link trends to environmental processes
- Ignoring units: Always include units when quoting data
- No evaluation: Section B requires balanced assessment, not just description
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