On Average, how much time did you spend studying for the OAT (hours/week) and for how long (weeks, months?). I'm starting to studying for my OATs right now and I have about 6 weeks until my scheduled exam date -- is that enough time along with my classes? I am taking three science classes right now (bio-chem, cell molecular biol, and advance physio). In 6 weeks, do you recommend reading the whole kaplan book?