IB ESS Paper 2 Strategy

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:

1. Identify the variables and their units
2. Describe the overall trend or pattern
3. Quote specific data points to support your description
4. 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

For more exam strategies, see our guides on IB ESS Paper 1 Strategy and ESS Case Study Questions Explained.