How to Score Full Marks in Criterion C (Personal Engagement) for the IB Math IA
Criterion C is one of the smallest sections of the IB Math IA by mark value—and one of the easiest to misunderstand. Worth just 3 marks, it often determines whether an otherwise solid IA feels authentic or mechanical.
Personal engagement is not about personality. It’s about decision-making.
Examiners aren’t asking whether you enjoyed the math. They’re asking whether you owned it.
What Criterion C Is Really Measuring
At its core, Criterion C answers one question:
Does this investigation clearly belong to the student who wrote it?
To award full marks, examiners look for evidence that you:
- Made meaningful choices
- Explored ideas beyond a template
- Reflected on outcomes, not just results
- Responded to challenges rather than avoiding them
A 3/3 IA feels directed, intentional, and thoughtful. It doesn’t feel copied—even if it uses standard mathematics.
Personal Engagement Starts With Ownership, Not Originality
A common myth is that Criterion C requires a “unique” topic. It doesn’t.
You can score full marks with a familiar idea—statistics, modeling, optimisation—if your approach shows ownership.
That ownership usually starts with why you chose the topic.
When a student investigates something connected to their interests—sports, music, economics, gaming, architecture—the engagement shows naturally. Not because the topic is impressive, but because the thinking is motivated.
Examiners can tell when a topic was chosen because it felt safe. They can also tell when it was chosen because the student genuinely wanted answers.
