How IB ESS Exams Are Marked

Understanding how IB ESS exams are marked gives you a significant advantage. When you know exactly what examiners look for, you can structure your answers to maximise marks.

How IB marking works

IB ESS exams use a combination of point-based marking and marking-band criteria:

• Short-answer questions (1-4 marks): Point-based. Each correct point or explanation earns a mark.
• Extended-response questions (7-9 marks): Use marking bands. Examiners assess the overall quality of the response against band descriptors.

Paper 1 marking

Paper 1 is a case-study paper. Short-answer questions use specific markschemes with acceptable answers listed. Examiners look for key terms and concepts. Higher-mark questions use marking bands:

• Band 1 (1-3 marks): Descriptive, limited use of ESS concepts
• Band 2 (4-6 marks): Some analysis, good use of concepts, some evaluation
• Band 3 (7-9 marks): Strong analysis, clear evaluation, well-structured argument

Curious how your own answers would score? Our IB Past Paper Feedback tool applies the same marking criteria and shows you a mark-by-mark breakdown.

Paper 2 marking

Paper 2 focuses heavily on data interpretation and scientific skills. Examiners award marks for:

• Correct identification of trends and patterns
• Accurate data references with units
• Linking observations to ESS concepts
• Evaluation of methodologies and data limitations

What earns top marks

Top-scoring answers share common characteristics:

• Clear, logical structure with paragraphs
• Accurate use of ESS terminology
• Specific examples (named case studies or data)
• Balanced evaluation with a clear conclusion
• Direct response to the command term

Common reasons students lose marks

• Not answering the specific question asked
• Missing key terminology
• No evaluation in extended-response questions
• Vague or generic examples