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IB Core: Getting to the Heart of the IB Diploma Programme (IBDP)

IB Core: Getting to the Heart of the IB Diploma Programme (IBDP)
Tanya Olander

Each year, around this time, grade 10 students worldwide and their parents are considering their course options for the last two critical years of their secondary education.

As the only not-for-profit K-12 school in Ho Chi Minh City to offer the IBDP, AP courses, and our own rigorous academic courses, students at SSIS have many options to consider.

Through the ten attributes of the IB learner profile, The mission of IBDP is to guide students to become inquiring, knowledgeable, caring, and internationally-minded people who recognize their common humanity and shared guardianship of the world and strive to make it a better and more peaceful place.

This piece highlights the IB Core, a unique element of the International Baccalaureate Diploma Programme (IBDP).

IB Core

The IB curriculum comprises six selected subjects and, at the center of the IBDP is the IB Core. If the IB subjects are the “brain” of the program, you can think of the IB Core as its heart. 

IB Programme model

The IB Core is central to the IB Diploma Programme.

The IB Core aims to “broaden students’ educational experience and challenge them to apply their knowledge and skills.”( and consists of three required components: Theory of Knowledge, the Extended Essay, and CAS (Creativity, Action, Service).

Theory of Knowledge (ToK) 

“How do we know what we know?” “Who owns knowledge?” “What makes a good explanation?” These are just some of the questions students learn to ask and reflect on in their Theory of Knowledge class

In ToK, students practice deep critical thinking and learn to question everything—not to prove things "wrong” but to understand why they might be accepted or considered “right.”

Female student behind chess board

A student presents her project at the TOK Exhibition 2022.

“I think ToK is different from all my other courses. It is learning about learning, and you have to think for yourself and detach yourself from the very basic assumptions,” shares IBDP student Minh.

The Extended Essay

The Extended Essay (EE), a self-directed piece of research that students work on independently, culminates in a 4,000-word paper and gives students the chance to complete their first major research paper with the guidance, feedback, and support of an advisor. This work prepares students for the research they will be expected to do on a regular basis at university. Thia Ostrander, SSIS alumna, Class of 2022, is now a student at Barnard College. Below, she shares how the EE has helped her this first semester at university.

Class of 2022 alumna, Thia, currently a student at Barnard College shares of the Extended Essay helped prepare her.

“While the EE process was one of the most time-consuming and challenging parts of the IB for me, it has proven to be the component that taught me the most practical skills for academic writing at university.

The processes of formulating a research question, carrying out independent research, and writing the essay itself taught me fundamental academic writing skills that helped reduce my learning curve at university. It also taught me how to approach a topic in an interdisciplinary manner and respond in a way that would add to the research field rather than reproducing existing analyses.

Finally, completing a task as large as the EE has made approaching university term papers less daunting, as they're generally much shorter than the EE.” 

Creativity, Activity, Service (CAS)

IBDP students also engage in the arts and creative thinking, with the goals of developing a healthy lifestyle and incorporating service to meet a genuine need in the community. At SSIS, students are supported in these endeavors by a dedicated CAS Coordinator and CAS Advisor.

CAS requires students to participate in a range of purposeful activities and at least one project. These should involve “personal challenge; thoughtful consideration, such as planning, reviewing progress, reporting; and reflection on outcomes and personal learning” ( 

The three strands of CAS (creativity, activity, service) focus on students’ personal and interpersonal development and emphasize experiential learning and self-discovery through:

  • Creativity - arts or other expressions that involve creative thinking
  • Activity - physical fitness or excursion contributing to a healthy lifestyle or
  • Service - an unpaid volunteering opportunity 

 “CAS is an important factor in balancing the intellectually challenging IBDP components, Theory of Knowledge, and the Extended Essay. A huge variety of impactful initiatives at SSIS, such as Heart Says Free Move, Hearing Vietnam, and Unity Impact was the direct result of students’ CAS work,” says HS Learning Program Coordinator Tucker Barrows.

Learning More About IBDP & IB Core

Students who choose the IBDP will most certainly be challenged academically, and as the IB Core illustrates, there is equal emphasis on the importance to continue growing as an individual, practicing the SSIS Core Values of Dedicated Service, Sense of Self, and Balance in Life as they are guided in preparation for the next steps in their academic careers. 

Families who would like to learn more about the IBDP course options in our High School or see the AP and SSIS Course pathways, please visit our High School page. SSIS families who need additional support are welcome, as always, to contact their child’s dedicated high school counselor.


Thank you to Tucker Barrows who contributed to this article.

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