Introduction
The Internal Assessment (IA) is a major part of IB Environmental Systems and Societies (ESS). For both SL and HL students in the 2026 first assessment, the IA gives you the chance to design and carry out your own investigation into an environmental issue.
The ESS IA is worth 25% of the final grade at SL and 20% at HL. Because of this weight, a strong IA can make the difference between a 6 and a 7. Understanding what the IA is and how it is marked is essential to achieving top marks.
Quick Start Checklist for ESS Students
When preparing your IA, make sure you:
- Choose a clear research question.
- Collect and process primary data (and sometimes secondary data).
- Apply ESS concepts to your investigation.
- Address strengths, weaknesses, and limitations.
- Follow the marking criteria carefully.
What Is the ESS IA?
The IA is an individual investigation based on fieldwork or laboratory work. It must:
- Be student-designed (not a teacher-led experiment).
- Collect quantitative or qualitative data.
- Relate directly to the ESS syllabus.
- Show systems thinking and evaluation.
Examples of IA topics:
- The effect of light intensity on photosynthesis in aquatic plants.
- A comparison of water quality in two local rivers.
- The impact of urbanization on biodiversity in green spaces.
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
- Choose a focused research question. Narrow questions are easier to manage and analyze.
- Plan data collection carefully. Reliable, sufficient data is essential.
- 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:
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