What is the IB Core?

Apart from the six subject groups, the IB consists of three core subjects which all students are required to pass in order to receive an IB Diploma: Theory of Knowledge, the Extended Essay and CAS.

Theory of Knowledge

In Theory of Knowledge (TOK), students reflect on the nature of knowledge, and on how we know what we claim to know. This is done through asking knowledge questions in the different subject areas. TOK is composed almost entirely of questions that help students to gain awareness of their personal and ideological assumptions. TOK offers teachers and students the opportunity to reflect critically on the diverse ways of knowing and the areas of knowledge while considering the role and nature of knowledge in their own culture, as well as in other cultures.

TOK provides coherence for students by linking academic subjects. It demonstrates ways in which students can apply their knowledge with greater awareness.

Extended Essay

The Extended Essay is a mandatory, independent research culminating in a 4000-word paper. The Extended Essay prepares students for undergraduate research, while simultaneously providing them with an opportunity to investigate a topic of special interest. This process helps students develop the capacity to analyse, synthesise and evaluate knowledge.


CAS, or Creativity, Action and Service, requires students to take part in a range of experiences as well as a final project. The Creativity strand focuses on any creative activity, such as music, art, dance, etc. Action is any physical activity, and Service requires students to research a need in the community and volunteer their time addressing the issue. All three strands are compulsory, with the purpose of creating balanced individuals who understand their responsibility as global citizens.