Adderall works very well. Whenever you get home from your classes take a nap and then take some adderall, you can go for several hours with limited breaks inbetween. And it doesn't really cause side effects, just ease yourself into it at first and you should be fine. Whenever I need to cram I take twice my prescribed dose and nothing negative happens to me, in fact it often gives me enough energy to finish early and start a different project.