Hopefully you will get advice from people with more recent knowledge, but I figured I'd chime in anyway.
This is assuming that what is tested is in line with the student's major so they've been working with chemistry, biology, etc the entire time.
No experience with MCAT. In Aus, we have UCAT (previously UMAT) and GAMSAT for undergrad and postgrad entry pathways and my eldest sat the UMAT deliberately without preparation other than the example questions given by the organising body (she did study English, maths, biology, chemistry, physics and economics in high school) because she used the test to decide if she really had the aptitude for medicine (she scored 98 which made her confident to study med).
MCAT applicants who haven’t studied biology or chemistry could prepare by getting human biology and organic chemistry textbooks and reading the relevant chapters for Biological and Biochemical Foundations of Living Systems and Chemical and Physical Foundations of Biological Systems.
