What Is the ESS IA and How Is It Marked? (2026 First Assessment)

How the ESS IA Is Marked

The IA is assessed against five criteria, each worth a set number of marks.

1. Research Design (6 marks)

• Clear research question.
• Relevant hypothesis or rationale.
• Appropriateness of method.

2. Data Collection and Processing (6 marks)

• Systematic collection of data.
• Sufficient quantity for analysis.
• Clear processing (tables, graphs, calculations).

3. Analysis (6 marks)

• Identification of trends and patterns.
• Explanation using ESS concepts.
• Linking data to the research question.

4. Conclusion and Evaluation (6 marks)

• Justified conclusion based on data.
• Identification of strengths and weaknesses.
• Suggestions for improvement and extension.

5. Communication (4 marks)

• Clear structure and presentation.
• Appropriate use of terminology.
• Proper referencing and citation.

Total: 28 marks

Common IA Mistakes

• Research question too broad or vague.
• Poor data collection (not enough data or unreliable method).
• Lack of processing (raw data presented but not analyzed).
• Evaluation is too short or generic.
• Overuse of background theory instead of focusing on the investigation.

What Examiners Look For

• Clarity: Is your research question specific and focused?
• Application: Do you apply ESS concepts, not just biology or geography?
• Critical thinking: Do you recognize limitations and suggest improvements?
• Communication: Is your IA well-structured and easy to follow?

FAQs

1. How long should the ESS IA be?
About 1,500–2,000 words, though there is no strict word limit. Quality is more important than length.

2. Do I need primary data?
Yes. Primary data (from fieldwork or lab work) is essential. Secondary data can support it, but cannot replace it.

3. Can my IA overlap with another subject?
Yes, but it must be assessed as ESS. Avoid making it purely biology, chemistry, or geography—always link back to ESS systems.

Exam Tips

1. Choose a focused research question. Narrow questions are easier to manage and analyze.
2. Plan data collection carefully. Reliable, sufficient data is essential.
3. Don’t skip evaluation. Weak evaluations cost many students marks.

Conclusion

The ESS IA is your chance to take ownership of your learning and show examiners that you can think like an environmental scientist. By designing a clear investigation, collecting and analyzing good data, and writing a critical evaluation, you can maximize your marks in the 2026 first assessment.

RevisionDojo Call to Action:
Need step-by-step guidance on writing the ESS IA? RevisionDojo’s IA resources give you templates, examples, and marking breakdowns to help you achieve your best score.

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