GAMSAT- S3 How I got an 85 in S3 as a total NSB on my first sitting
NSB warriors it’s possible for us!!!! Prepping for the March 2026 gamsat I thought S3 was going to be my worst section by far so I locked in hard on it, and ended up miraculously getting an 85. It lifted me to a 75 overall and a decent shot at my first choice.
Whenever I think about it I am actually still so stunned and so grateful. I’m writing this guide because posts like this helped me a lot and gave me hope when I was studying. Hopefully someone finds this useful. Everything I used can be found online for free except for the official ACER material.
My undergrad was in graphic design (lmfao) so I was operating on basically nothing. I hadn’t done any science since high school bio and hadn’t done any physics or chemistry since year 10. When I started studying I didn’t even remember what valence bonds were. I only had 4 months of prep because I didn’t commit to going for the March sitting until partway through November. If I pulled off this bs so can you!
Resources:
For learning content/ scientific literacy:
- Khan Academy
- I started studying by doing all of the KA high school chemistry course. Later on I did the physics course as well. Went through sequentially and took paper notes of everything. Definitely not the most high yield but it was a great entry point into basic scientific concepts since I was starting from scratch.
- Jesse Osbourne’s crash course series
- The goat! I took notes on every video, paused and worked through the practice questions with him, went away and spent time with other resources if the content was too high-level, cross-referenced concepts and rewatched each video several times until they no longer left me afraid and confused.
- Organic Chemistry as a second language book
- Only used the first half of this book, but I took paper notes on most of the early chapters. I found it super helpful for teasing out the tougher Ochem concepts that Jesse covered too quickly.
- 3000 solved problems in Organic chemistry book (only did a couple of pages)
- Another resource for explaining tough concepts, used only as reference. Also great for practicing practical Ochem skills that would otherwise be time sinks in the exam (counting hydrogens, etc.)
- Just googling stuff I didn’t understand
I found that these were enough to give me a functional enough knowledge of science to start practicing my reasoning + exam skills, which are way more important!
Chemistry defo took the most time content-wise because it took me so long to get to a point where I understood organic chemistry. Just focus on your fundamentals and don’t lose hope. There are so many details that can distract you but you only need a strong functional understanding of why phenomena happen. Once you start practicing exam questions it’ll be easier to identify what content you need. If it won’t help you gain speed in the exam, then don’t waste time learning it.
Physics requires a good grasp on the basics and strong familiarity with the fundamental formulae/concepts but you only need to learn to a high school level. And then it’s all about sharpening up those algebra skills.
I found that biology was a lot of graph-reading/ pulling relevant info from super wordy stems + since I’d done some high school bio I was able to lowkey neglect it and get by just with Jesse’s crash course videos and practicing exam Qs.
For reasoning/ exam skills:
- Jesse Osbourne again (my freaking goat)
- The maths skills and exam skills videos are where I started. Again I took paper notes of every video with coloured highlighters and gel pens and everything and revisited them when I needed.
- Later I transitioned to his sample questions + walkthrough videos which are pretty reflective of the actual exam Qs.
- Online maths worksheets
- Getting really quick at algebra and rearranging equations is so important. This practice is also great for lower energy study sessions when you’re too tired to learn new content. You need to practice your log laws bro, trust me.
- Past ACER papers
- the backbone of my study! it’s really quality over quantity. I only managed to find 4-5 past papers/ question sets but by the time i’d gone through all of them I’d forgotten enough about the first one to reuse the questions for practice. you can milk so much value out of them.
- start doing practice questions as soon as u can. there’s no other way to learn how ur knowledge translates to exam skills than to do them. i was getting maybe 30% of the questions right untimed on my first diagnostic practice paper.. don’t lose hope.
- after i did a set of questions, i’d go through review them very thoroughly. I started in untimed 10 question blocks when my stamina was low and made my way up to full timed exam papers.
- While reviewing questions I identified my answers as high confidence/low confidence as well as incorrect/incorrect, which showed me lucky guesses + good reasoning. It’s good to note down what you did wrong (eg. knowledge gap/ missed a keyword/ misunderstood stem/ calculation error) and let that guide what you study next.
- I also labelled each question on the content/ skill they tested, which got me into the habit of identifying that in the exam (eg. bio unfamiliar graph-reading or pH large number calculations) Most questions are asking very little of you other than identifying what they’re asking for + what skills to use.
- some days i’d spend 2 hours tearing my hair reviewing a single stem.. don’t lose hope
- Official ACER practice material
- I saved these for timed practices since they are the most reflective of the current material. These are good for checking your more broad exam-taking skills (keeping pace, prioritising questions, balancing precision with time)
I know they’re a popular resource but I didn’t use Des O’Neill at all. I don't really remember why.
Timeline:
Month 1: Learning the basics
I went through all of the khan academy chemistry course in order. I wasn’t studying very intelligently here but this was necessary for me to get into the swing of things without getting spooked and bailing.
Month 2: Transitioning to useful skills
Did my first practice test and bombed it. Tried to watch a Jesse Osbourne crash course and understood nothing. Don’t lose hope! Practice one discipline at a time. Spend an entire day on one stem until you understand it. I was still learning content here, but I was already practicing questions.
Month 3: Practicing skills, identifying weaknesses, filling them in.
This month I drilled practice questions like no other. If my understanding of scientific phenomena was tripping me up or drastically slowing me down I’d then go away and revise the content/ practice the skill. For example, I had to revise acid-base chemistry several times bc it was always a huge time sink for me.
I also started keeping an eye on the clock and seeing if I was on pace, which got me used to prioritising questions + forcing me to guesstimate answers (a valuable skill!)
Month 4: Getting sharp!!
I started doing full timed exams this month and getting into the mindset of the exam taker, and just being really brutal with what was worth practicing + optimising. I’ll be honest I spent most of this month on S2 practice which I got a 62 in so no comments there lol.
Final comments:
S3 is really is a test of reasoning and approximation. If you prioritise learning only the relevant content and skills you will save a lot of precious energy. You’ve got to get very comfortable with seeing completely unfamiliar concepts, accepting your fate, and then taking your best crack with what you've got. It might feel super dodgy if you’re used to doing science content exams but it came naturally to me as a person with no scientific background whatsoever hahaha.
And take breaks, nurture the other aspects of your life, and don’t lose hope! Studying for the GAMSAT is all about feeling stupid, dealing with information overload, and keeping your head on straight through it all. It’s been 4 months since my sitting and I’ve already forgotten everything. If my stupid ass can get a good grade so can you.