Hey Amanda!
I'm a terrible procrastinator, too. At this very moment I have fifty pages of English homework on my desk that I should be doing. And it's due tomorrow. -_-
Any-who, motivation!
There's short-term motivation, which is just a little reward for doing the homework and the consequences of not doing the homework. For example:
-If I finish my math, I can have a break to get a snack!
-If I don't finish my math, the teacher will give me a zero tomorrow, and I'll be disappointed in myself.
Then there's long-term motivation. Is there a particular job you're interested in after you graduate? How much additional education does it require? Plus, there's always the general satisfaction of working hard to understand something and FINALLY getting it right!
Knowledge stays with you and you never know when it's going to come in handy, even if you feel like it's pointless right now.
Additionally, background music can help. Choose music you already know well so that you don't get distracted listening to it. (If you try this method and it just distracts you more, drop it. :P)
It might also help to have a little snack or something caffeinated. I usually get a cup of coffee or tea and drink it while I'm doing my homework, or have some chips and salsa on my study break.
*sips coffee thoughtfully and returns to English homework*