Rubric Guide
Rubric Guide
Understand what the IB is actually asking for.
Each criterion explained in plain language — with examples and a checklist for your next revision.
What IB expects from you
Evaluation
Evaluation is not just saying what went wrong. You need to explain how each limitation actually changes what you can conclude.
What a weak answer looks like
“The temperature may have changed during the experiment.”
What a stronger answer looks like
“If the temperature varied during the experiment, enzyme activity could also have changed. This would affect the reaction rate at each pH and make the trend less reliable, because temperature is a confounding variable.”
In plain language
Evaluation is not just saying what went wrong. You need to explain why it matters.
A weak evaluation lists errors. A strong evaluation explains how each error changes what you can conclude.
Before your next submission — Evaluation
- 1Name the limitation clearly.
- 2Explain how it affected your data (not just that it might have).
- 3State whether it affects reliability, validity, or precision.
- 4Suggest one specific improvement for future experiments.
Explanations are based on IB Biology IA criteria. Confirm with your teacher for other subjects.