Explained
What are TOK, the Extended Essay, and CAS in the IB?
The 'core' is what makes the IB Diploma more than six subjects: Theory of Knowledge (TOK), a course on how we know what we know; the Extended Essay (EE), a 4,000-word independent research paper; and CAS (Creativity, Activity, Service), 18 months of documented engagement beyond the classroom. Together they can add up to 3 bonus points.
The core is the IB's signature: the Extended Essay builds genuine research and academic-writing skills before university, and admissions officers consistently cite this as matching what they expect on day one of a degree.
It is also real workload — TOK deadlines, an EE, and CAS reflections run alongside six subjects, which is why the IB suits students who handle sustained, distributed work rather than only concentrated exam sprints.
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