What is the hardest IB Class?!

Written by Aarya Armogan, 10/06/2026. 

What is the hardest IB Class?

Well, according to the May 2026 grade boundaries here are the hardest classes. Before that let’s explain what a grade boundary is. An IB grade boundary is the minimum mark needed to achieve a specific IB grade, in this case a 7 (the highest IB mark). Boundaries can vary between subjects and exams depending on the difficulty of the assessment. 

So for ESS HL, getting a 64% or higher between your paper 1, paper 2, and practical work, would equate to an IB 7 on the report card. Now let's look into this a bit more so we can understand why the boundaries look like this…

As you can see above, ESS and SEHS are mentioned multiple times, so why is that? 

For ESS, the updated IB syllabus was launched for teaching in August 2024 and was featured in assessments for the first time in May 2026 (Revision Dojo, 2026). This means that past papers will not be in line with the new syllabus, and thus students will have to use the IB Specimen Papers to get relevant practice for the new syllabus. Major changes to the course include the introduction of HL and SL, the three lenses for higher level studies, and new IA requirements.

As for SEHS, its updated IB syllabus also launched in 2024 and was featured in exams in May 2026. The syllabus was moved into three main themes, optional content was removed from the syllabus, and there is a new collaborative project (ManageBac, 2024). As I said before, with the new syllabus, past papers will no longer be relevant, and students will have to rely on Specimen Papers.

So, this explains why courses that generally have smaller grade boundaries appear to be very hard. It is also super important to remember that the IB is graded based on grade boundaries, so some years a course may be harder or easier than preceding years!

Now, what about the others?

Marine Science is a lot less common compared to classes like ESS, Global Politics, or Physics. Because of this, students may have fewer resources available to them when studying. There may be fewer past papers, study guides, online resources, and other students discussing the course compared to more popular subjects. This does not necessarily mean that Marine Science is harder, but it does suggest that the resources available to students are correlated to how difficult a course appears statistically.

Physics also has a very large grade boundary, but as an SL subject, so why is that? One possible reason is that Physics is a required science for some students depending on their career plans, but not every student who takes it will necessarily be very strong in the subject. These students would naturally be more likely to take Physics SL instead of HL when they have the choice. This can make the student population taking the course different from a subject that students choose because they are already interested in or strong at that subject.

Global Politics is a subject where answers can be more subjective when compared to subjects like Physics. Students have to understand political concepts, use examples, explain perspectives, and create arguments. Two students could know the same information but receive different marks depending on how well they explain and apply their knowledge. So, that might be why we see such a large grade boundary.

Now that we have looked into every subject in the top 5, what subject is the hardest?

In my opinion, there is not one hardest subject. The grade boundaries change every year, and the May 2026 boundaries are indeed interesting because ESS and SEHS were being assessed under their new syllabi for the first time, changing the grade boundaries for the subjects. Moreover, the amount of resources available to students can also change how difficult a course appears, especially for less common subjects like Marine Science. Even the students taking a course can affect how we interpret the boundaries, as I discussed for Physics.

So, while looking at grade boundaries is a fun way to compare subjects, it should not be used as a ranking of the hardest classes. A course with a low boundary does not mean it is easier, and a course with a higher boundary does not mean it is harder. There are too many other factors involved. The hardest class can change depending on the year, the syllabus, the assessment, the resources available to students, and the student taking the course.

• Aarya :) 

Works Cited

Hetherington, Thomas. “New DP Sports Exercise and Health Science (SEHS): What to Expect.” ManageBac, ManageBac, 9 April 2024, https://www.managebac.com/subject-support/new-dp-sports-exercise-and-health-science-sehs-what-to-expect.

RevisionDojo Team. “IB ESS 2026 Syllabus: What’s New and How to Prepare.” Revision Dojo, Revision Dojo, https://www.revisiondojo.com/blog/the-new-thing-about-ib-ess-what-to-expect-from-the-2026-syllabus. Accessed 28 September 2026.