I don't know how it works when you buy from an online seller, but I would think they must ask for some kind of verification.
If you buy the software at a college bookstore, which you can do on many campuses, you would, of course, just show your student ID card.
You might check a college bookstore. I know one major university where students can get Win XP, Office 2003, and FrontPage 2003, all for $100.