The best tips I have for you is to take time after school, stick around there or go to a public library(or any other place where you feel comfortable and relaxed). Have nothing but the school-work in front of you, sit down and give it your time.
I can't get shit done once I get home. I'll get sucked up by whatever and can't dig my assignments out of the back of my head again, for anything. The best way to tackle this is to isolate yourself from conflicting interest, by relocating yourself to somewhere isolated from other possible activities.