Ask him if he's interested in hanging out with you during lunch, or after school. Maybe meet up on a weekend. Or you could ask if he has a myspace/facebook something like that so you two can talk.

The most difficult part is finding the courage within yourself to ask. Asking is a relatively simple process that involved a sentence or two. What I suggest is simply opening your mouth and saying what you want to say. The first few times doing this is incredibly awkward, unnatural and uncomfortable, but eventually it becomes easier to do. As for what to say, I agree with the poster above. On a personal level I'd recommend avoiding using the terms 'date' and 'going out'. It can put both of you on edge. Using 'hang out' instead, in my opinion, smooths out the process for both parties and increases the odds of something coming out of the whole ordeal.

yeah, you should use hang out and not date.
Also how old are you?

I think you should start off with talking to him on the phone, or msn .. get to know eachother more and get close before asking him out =.= ... and then ask to simply hang out soo start off slow and steady m'dear.

Girls shouldn't ask guys out.

It's actually more common for girls to ask guys these days. I don't see any problem with it, and a lot of guys who aren't quite as confident would appreciate the release of stress because the girl initiated a conversation or asked him out.