Free/Alternative Resources to Study for Section 3

There is no shortage of 3rd party preparation courses trying to take your money and plenty of offer resources that that contain information that you can easily find on the internet. Many of these preparation companies like to sell you text books to increase you science knowledge but, in all honesty the information they provide is either lack luster or the same as any other textbook. I've compiled a list, separated by levels of experience, of free/alternate resources you can use to save yourself some money.

You will notice my reliance on MCAT sources, this is because the MCAT contains, in my opinion, the exact same science subjects. To make sure you don't spend more time learning the sciences when you could be practicing questions, which I believe is more important. The GAMSAT doesn't test recall but your ability to solve the problem from the questions. Since this is science, someone with greater background knowledge will have an advantage so it is also beneficial to develop this.

The natural progression is down and it may also be on a subject basis, if you find yourself struggling or excelling you may wish to regress or progress. 

Know nothing about the science

Free: Khan Academy 

More specifically its MCAT Test Prep playlist, it does contain some social science and humanities topics (which you may find useful in section 1). If you wish to study specifically for section 3 you can omitt these topics. Khan Academy is almost perfect, it gives you the basics required and is delivered in a way anyone can learn, maybe not the best for hard core MCAT study but definitely sufficient for the GAMSAT. I recommend watching every video and taking notes as if it was a lecture, read the articles and the do the questions to test your knowledge. Their questions usually aren't that difficult and is a good change from just watching videos. 

Since this is a selected playlist from their huge collection of topics, some of their videos will jump into more advanced topics and for someone without background knowledge may find it hard to understand. If you are willing to spend the time you can watch their entire science collection or just specific concepts.

Paid: Kaplan MCAT Books

The site that I linked to contains mock exams for the MCAT aswell, all you need is the science text books and they don't need to be new editions. Again just like Khan Academy you may omit the critical analysis and reasoning book if you just want section 3 study. Buying these books compared to the free alternative I've provided won't give you a huge advantage, I've done a review for the books which you can see on the reviews tab, but the information is much denser with more questions that you can use to target specific weak areas. Unfortunately these questions are MCAT style, if you are looking for GAMSAT style questions with theory, a similar book would be the Gold Standard books (I have also done a review). The questions are good but the rest of the content is inferior to the Kaplan books. 

Learned about the sciences but forgot

This requires Anki, which is free on windows and mac but you would have to pay to go mobile. u/MileDown on reddit is extremely popular for sharing his flash cards that he used to study for the MCAT. The original post is here and the shared link is here. Inside the deck is heaps of cards, along with Anki's recall timing, which it has become so popular for, it is a great way to relearn the concepts you have forgotten. You don't need to do everything in the deck, hes included humanities and essential questions which is not required for GAMSAT section 3. You can obviously go through the resources I've mentioned earlier but this is an alternative and you won't have to spend as much time to regain your memory.

Has background information about the sciences and would like to revise

From the exact same user, he also released review sheets here and the download link here. All you need to do is read over them and just pay attention to definitions and concepts no need to memorize anything new. You should also have your own notes you can go through but this is another point of view.