How to get through school on little sleep?

its 1:46 and im slowly falling asleep. i bet ill be out by like 2:30 or 2:45. i have to get up at 6 to go school, which i dread enough already, even with enough sleep. how do i make it through school without falling asleep during it or being late? no, i cant miss school, ive missed 12 days already due to swine flu and getting my tonsils out