Can I switch my IB science after the first term?

In most schools, switching an IB science is possible only very early, and it’s painful even then. The courses move quickly, and missing foundational topics creates gaps that multiply later (especially in Chemistry and Physics). If you’re considering a switch, do a small diagnostic: attempt a short set of topic questions and see whether the issue is content, technique, or motivation. If it’s technique, you may not need to switch at all. Use RevisionDojo’s Questionbank to test a topic under time, then use AI Chat to unpack exactly why marks were lost. A smart decision is based on evidence, not panic.

Do I need to take IB science at Higher Level for university?

Sometimes yes, sometimes no, and the only reliable answer is your target course requirements. Medicine-related paths often expect Chemistry HL, while engineering often expects Physics HL. But plenty of degrees accept Science at SL, especially if your overall profile is strong. The hidden issue is that IB HL science also increases weekly workload through depth and pace, not just “more content.” Before committing, map your week honestly: can you sustain daily recall plus weekly timed practice? If you’re unsure, check university recognition patterns in RevisionDojo’s guidance and ask a tutor for a realistic plan.

Should I take two IB sciences?

Taking two IB sciences can be strategic, especially for competitive STEM pathways, but it’s also a workload decision. Two sciences means more labs, more IA planning pressure, and more exam technique to maintain at once. The students who do best with two sciences usually run a tight system: Flashcards daily, Questionbank sets several times a week, and timed papers early. RevisionDojo helps here because your Biology, Chemistry, and Physics workflows can live in one place, so you’re not rebuilding your system per subject. If your motivation is “keeping options open,” that can be valid, but pair it with a calendar and a routine.

Which Science Should I Take in IB? Bio vs Chem vs Physics

RevisionDojo Team

•7/26/2025•6 min read

Choosing your IB science can feel like picking a door in a hallway you haven’t walked down yet. You hear opinions at lunch. You read a few forums. Someone says, “Physics is impossible,” and suddenly your future seems to hinge on a single timetable choice.

But the truth about IB Biology, Chemistry, and Physics is quieter: each is difficult in a different way, and the “right” choice is usually the one that matches how your brain likes to work under exam pressure.

IB Science Choice Checklist (quick, honest, useful)

Before you decide, run this IB checklist:

Do you prefer memorising and explaining (Biology), multi-step problem solving (Chemistry), or models + maths (Physics)?
Are your university goals likely to require a specific IB science?
Do you enjoy lab work, or do you just tolerate it?
Can you commit to a weekly routine of Study Notes -> Flashcards -> Questionbank -> timed practice?

If you want broader context on what makes exams feel hard, read How Hard Are IB Exams? A Realistic Guide.

Biology vs Chemistry vs Physics in IB: the clearest comparison

IB Biology

IB Biology is the subject of living systems: cells, genetics, evolution, ecology, and human physiology. It often rewards students who can build clear explanations from detailed content.

Best fit if you like:

learning processes and writing them clearly
linking diagrams to explanations
steady, spaced revision (because forgetting is fast)

Start here: IB Biology Resources and IB Biology Revision Notes (SL/HL).

IB Chemistry

IB Chemistry sits in the middle: conceptual ideas, calculations, and lab precision. Many students find it fair but unforgiving: small method errors can cost marks.

Best fit if you like:

structured problem solving
practising until steps become automatic
learning patterns (stoichiometry, energetics, equilibrium)

Build your base with IB Chemistry - RevisionDojo and sharpen exam technique with Breakdown of IB Chemistry Marking Schemes.

IB Physics

IB Physics is a logic-and-models course. You’re often turning a real scenario into an idealised model, choosing an equation, and executing clean maths under time pressure.

Best fit if you like:

algebra and rearranging formulas confidently
drawing diagrams and extracting relationships
puzzles where understanding beats memorising

Use Physics - IB Resources and the practical advice in IBO Physics: How to Succeed in the IB Physics Course.

Which IB science is easiest (and why that question backfires)

In IB, “easy” usually means “easy for my learning style.”

Biology can feel easiest if you revise little-and-often with Flashcards.
Chemistry can feel easiest if you enjoy method marks and repeatable steps.
Physics can feel easiest if maths is your comfort zone and you like clean models.

If you’re tempted to choose purely on difficulty, read Which IB Science Is the Easiest? A Detailed Guide and The Hardest Science Subjects in IB: A Comprehensive Guide.

Choose your IB science by university goals (simple guide)

Some degrees treat IB science choices like prerequisites, not preferences.

Medicine / biomed: often Chemistry HL, sometimes Biology HL too
Engineering / physics: often Physics HL
Environmental pathways: often Biology (and sometimes ESS, depending on school)

For a bigger picture, use Which IB Science Subject Has the Best University Recognition.

How to study whichever IB science you pick

The highest-performing IB students look boring in one specific way: they keep the same loop.

Study Notes to get clarity fast
Flashcards for daily recall (definitions, processes, equations)
Questionbank to turn knowledge into marks
AI Chat + Grading tools to find what the markscheme wanted
Mock Exams + Predicted Papers to train timing and stamina

RevisionDojo is built for this system across sciences: Questionbank, Study Notes, Flashcards, AI Chat, Grading tools, Predicted Papers, Mock Exams, Coursework Library, and Tutors.

Conclusion: pick the IB science you can practise consistently

The best IB science isn’t the one your friend called “easy.” It’s the one you can revise steadily, practise under time, and improve in week by week.

If you want a calmer way to choose (and then score higher once you’ve chosen), make RevisionDojo your home base: start with Study Notes, lock knowledge with Flashcards, prove it in the Questionbank, then pressure-test with Mock Exams and Predicted Papers. Your IB choice matters, but your IB system matters more.

Which Science Should I Take in IB? Bio vs Chem vs Physics

Which Science Should I Take in IB? Bio vs Chem vs Physics

IB Science Choice Checklist (quick, honest, useful)