I had a study trick that I used in college.
At the beginning of the semester, I assigned every subject its own music. Usually a single CD, 60 -70 minutes of music. Whenever I was studying that subject I would listen to the assigned music. All semester long. I would use headphones and play the music fairly loudly.
It had to effects. First, it helped to keep me alert while studying... But even more importantly, I would listen to the same music for an hour or so before taking an exam.
You would be amazed how you can use music to enhance recall.
The downside is, once the semester is over you might as well just throw the CD away... You won't ever want to listen to it again.