How the IB works: Understanding the International Baccalaureate Curriculum

Confused about the IB and not sure how it actually works or whether it would be the better curriculum for you? Not to worry, join us as we take a deep dive into everything IB! How it's structured, how it's graded and the benefits!

6 months ago   •   5 min read

By KIS academics
Photo by Erika Fletcher / Unsplash

What is the IB?

The International Baccalaureate, or more commonly known as the IB, is a secondary school credential founded in 1968 in Geneva, Switzerland. It was designed to provide a universal, standardised and more importantly, transferable diploma for students who would move abroad. It is now taught in over 3000 schools in 140 countries worldwide and is recognised globally by universities. In Australia, the program is offered by both public and private institutions. Some will offer a choice between IB or HSC while others designate themselves to only the IB diploma.

The IB advertises itself as creating global-minded and well-rounded students after the completion of the two-year diploma. It forces students to think creatively and work in a variety of subject areas to ensure they have the best preparation going into whatever career path they may choose.


The IB diploma consists of six core subject areas that every student is required to choose from. There is a wide variety of course options, however, your school may not offer all of them. These subject areas are:

  1. Group 1: Studies in Language and Literature (English)
  2. Group 2: Language Acquisition (Foreign Languages)
  3. Group 3: Individuals and Societies (Humanities)
  4. Group 4: Sciences
  5. Group 5: Mathematics
  6. Group 6: The Arts

All of these subjects are required, with the exception of The Arts which can be swapped out for an additional Science, Humanities, or Languages course.

This is one of the strengths of the IB curriculum as regardless of whether or not you know what career path you will go down, it prepares you for a wide variety of them while still allowing you to hone in on your interests. Universities look at this positively as they know IB students will be well-rounded and prepared for a variety of future challenges.

In your six subjects, you will have to designate three to be Higher level (HL) and the other three to be Standard level (SL). HL courses require about 240 teaching hours and SL courses about 150 hours, meaning there is a significant difference in difficulty. The decision about SL and HL classes should be made with a counsellor as certain career paths or universities require you to take specific courses. In general, there is a large overlap between IB classes and ATAR ones with some minor differences.

Grading and Exams

The IB course is divided into two years - DP1 and DP2 - but both years are still important. Your IB diploma score is determined by final exams at the end of DP2 (November in Australia, May in other countries) but your DP1 results are still important for predicted grades. These are grades given typically at the beginning of your second year and can be used to apply for conditional offers from universities in certain countries.

The IB grading system for each subject ranges from 1-7, with 7 being the maximum. This grade is mostly from the final exams at the end of DP2 which are externally marked by the IBO. A significant portion of it will be from an Internal Assessment (IA) graded by your teacher. Each subject has a different type of IA, (eg. lab report for sciences) and it contributes about 15-20% of your overall mark and is done in the first year usually.

What we mean to say is that you shouldn’t take your first year lightly. In your final exams, you will be tested on all the content you learned over the two-year course so be well prepared!


In order to pass the IB Diploma, you must achieve at least 24/45 points with at least 12 from HL subjects and 9 from SL subjects.

Apart from the six core subjects, there are three additional requirements to pass the IB.

  • Extended Essay (EE)
  • Theory of Knowledge (TOK)
  • Creativity, Activity, Service (CAS)

Extended Essay (EE)

The extended essay is a 4000-word independent research project in one of the 6 core subjects you take. You work with a supervisor periodically but this is largely something to complete on your own and can be done on any topic of your interest within that subject.

Theory of Knowledge (TOK)

Theory of Knowledge is an epistemology class that looks to explore deeper into how we know what we claim to know. Its main components are a presentation graded internally and a 1600-word essay graded by the IBO.

From these two requirements, you can gain up to 3 Diploma points in addition to the 42 available from your core subjects so it is important that you do well!

Creativity, Activity, Service (CAS)

CAS is an initiative designed to make sure students are not solely focusing on academics. CAS requires you to journal and reflect on different activities you do such as sports, volunteering, or different projects. Most students will be able to fulfil the passing requirements simply by doing their normal extracurricular activities.

IB or ATAR? Which is the best option for me?

The choice between IB and ATAR depends on a variety of factors both external and internal to the student.

If you know you might move overseas or to a different curriculum, it might be best to consider IB as it is standardised regardless of the country or region. If you are considering studying overseas, IB is preferred as all universities are familiar with its scoring and courses as opposed to ATAR.

However, some students in Australia choose IB because of the generous grading when converting into ATAR or simply because they are looking for a different challenge. It generally suits students who are well-rounded and can adapt to different challenges presented by the different subject groups. If you want a full detailed analysis of how IB differs from ATAR make sure to check out our blog post on that!

IB vs ATAR: What’s the difference?
What is this elusive IB thing, you ask? How does it compare with the ATAR? And what is the best option for me? Well, you’re in the right place because we answer all those burning questions right here!

Speaking from personal experience, the IB Diploma has a lot to offer. It helps you advance in independent management, creative thinking and personal development mainly through the way it is structured. If you are still unsure about whether IB is the right choice for you, consider signing up for a free 30-minute study skills consultation with one of our many expert IB tutors.

Written by KIS Academics Tutor for IB English, Maths, Physics, Chemistry and Biology, Muhammad Ammar. Muhammad will be pursuing a future in medicine and has received stellar reviews from his past KIS academic students. You can view Muhammad’s profile here and request him as a tutor.

Want more personalized study guidance to help drastically improve your marks? A private tutor can make the biggest difference!

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