from your situation, i think he might be shy....take things easy....i was shy too once....i am in a long distance relationship so i can give you a few hints....i learned a lot about guys in love through my boyfriend but all guys are different......i still am shy but not that shy.
when he looks at you, wave HI while smiling if you guys are standing at a distance.....it will make him a little confident.....that s how guys know that they can make the move.
if you guys are standing kinda close....simply say "hi, how are you?....what class do you have right now?" and this should keep you guys talking for a bit.....then next time you guys meet, ask for his MSN or YAHOO id so u guys can chat in messenger or ask for his number.....u can tell him a cute pick up line "i lost my number, can i have yours?"
best of luck!!!