Hi,
Are these your Unit 1/2 marks?
I did Bio Units 1/2 and 3/4 but didn't do psych at all so I can only tell you about Bio.
If you decide to continue doing Bio figure out where it is that you're losing marks.
- Is it that you don't understand the content because of your teacher's learning style? If so consider getting a friend who's acing the subject to explain the concepts to you or try to find a really good tutor.
- Is it the way that you're answering the questions on the SACs? I struggle with this as well so I would reccomend taking your time to thoroughly read the question, think of your answer before writing anything, consider whether your proposed answer actually answers the question according to how many marks said question is worth and then write your answer. This process may seem time consuming or you may fear that you won't finish the SAC but it's worthwhile in my opinion as it ensure you're not overwriting which examiners don't like.
- Is it that you're not completing enough practice questions? (VCAA ones are best and complete them as you do each topic rather than leaving them for exam revision as they'll teach you early on how VCAA likes answers to be written)
By the way 38/46 = 83% is a great mark and shows that you have the potential. Importantly, your SAC marks in 3/4 Bio are important in so much as they determine your ranking. So figuring out the average mark and seeing where you stand in your cohort is probably more useful than looking at your marks in isolation. It may be that your school's just giving you hard SACs.
Good luck with your decision!