What kind of drawing? Do you want to do painting too? Image touch-up?
My Mac came with OmniGraffle for drawing, PixelNhance for color touchup, and GraphicConverter for image conversion.
iPhoto can do image touch-up.
If you didn't get AppleWorks with your Mac, it's cheap to buy, especially for a student. Its drawing module has limited features but has a nice design. I prefer it to MS Word drawing. The AppleWorks painting module is bare bones.
Preview can display almost any type of image file and it lets you crop, flip, and rotate.
Bottom line: There is nothing equivalent to Windows Paint, but you have a few choices depending on what you have in mind. There are freeware and shareware choices too.