Plan ahead of time:
-study in intervals
-choose specific days to study a specific topic (example: mon=bio, tue=calc, etc.)
-every so often takes breaks from studying so you don't overwork your brain
-when taking a break get up and move so you don't feel worn out (for example stretch for a few minutes or walk around the room)
*DONT STRESS EAT!!!!!!
-grab a little something that is healthy and will fill you up!
-choose something with protein like grains, nuts, fruits, vegetables, etc.