What do you do to focus?

Managing your time for studying is probably the most helpful thing. Setting deadlines and budgeting breaks for your self to get your mind of things for brief periods of time help. Switching topics/subjects alleviates the growing need to stray from studying if you are stuck on one topic for to long. Medically, Adderall is used by many people to focus in times that are needed (test, etc) but can only be prescribed by a doctor.

Take 10–30 minutes off and force yourself to relax. For me, it’s playing the piano, spending some time with my dogs, or grabbing a snack. Fluther, Facebook, computer games, etc. do not count. It has to be an activity that clears your mind. Half an hour of “slacking off” may seem like a lot, but I’ve found that the “reset” increases my efficiency more than spending that time struggling between work and distractions.

I’ve heard from others that the period right after some exercise is great for focusing and absorbing knowledge, but that’s never worked for me. Could be worth a try though.

I go for a walk,meditate,stretch,put some music on,then get back to it.

I had the same problem last week and asked a similar question.
A few things that helped me:

Making/drinking tea (Making it took my mind off what I was doing)
Listen to some low instrumental music, nothing with words because the words can distract you. If that doesn’t work, just open the window and listen to whatever is going on outside.
I’m not going to say “make a list” or “make an outline” because I know that never helps me. It actually confuses me more.
Take a nap and recharge. Your brain probably just needs a break.
Try not to think about what you have to do when you’re taking a break. Hopefully when you come back to it you can focus.

At a yard sale, i was lucky enough to find a set of noise-cancelling headphones. i mean you can barely hear yourself breath. it elimates are the outside noise completely. i use the headphones when i require absolute quiet, in order to study. music is a distraction to me and also other outside noises. the headphones are a blessing for me. they may not work for you, but see if you can borrow a set, before you purchase.

I would do the same thing when I was younger. Fortunately I realized that I was one of those people who could only concentrate under pressure. If I waited the night before and exam to cram and the morning of, I would ace the exam. My focus would be 100% when I knew time was limited. Of course I also did make sure to do a lot of discussion in class as well. I would retain about 90% of what I learn in class and only had to briefly refresh. The other 10% was the only thing I would have to quickly hard wire to my brain. It would usually be stuff breifly discussed in class.
Best thing is pay attention in class. Wish I could help you more but the best thing you can do now is at least pay attention to how you learn.
For now just tell yourself that nothing else is going to help you pass but to study.

Try going to the quietest place you can, or get a pair of the noise-cancelling headphones @john65pennington suggested. If that dead silence drives you nuts, try listening to some very quiet classical music (or something that won’t get you tapping you feet and singing along). A white noise CD might help.

For me, I need to eliminate or minimize all distracting stimuli.

I find I focus best in a work space set aside to that purpose alone.
I prefer to close the door to the room in which I am working.
I work best where the only sounds I hear come from me.
I try to eliminate all the potential distractions.

I work on one project or subject at a time and I plan out how long I will work before I take a break. I reward myself for staying focused and working effectively with a break of a planned duration during which I allow myself the reward of doing something I like or enjoying something I especially value.

You could masturbate, that will take your mind of things and you will be nice and relaxed to start again.

@xxii Actually took your suggestion and went to go buy frozen yogurt with some friends. When I returned I was able to focus – I guess all I needed was some fresh air. Thanks.

@Sophief I would have actually considered that if I had I not been sitting in the middle of a library, lol.

@Pandora Got a straight A on my exam – I really surprised myself with that one.