I'm sure you can just send them a check in the mail addressed to them. However, to make sure it gets there on time and properly, I would hand it in personally. Unless you live very far away.

Also, you should write Tuition - (Student Number) in the memo on the front.

yeah. always have your student number on everything! that's their way to track you down.
I would suggest handing it in personally if you can... you can't always trust the postal system... :S i've had bad experiences w/ them.