There are some posts higher up suggesting that paying education price for OS X requires you to use it for educational purposes. I see no evidence of this, merely that you have to be a student/teacher to be eligible to pay those prices. The aim, as I saw it, was to provide a lower bar to entry to the Apple platform for up-and-coming earners, and to encourage its adoption in education, not to apply an artificial restriction in exchange for lower price.
Otherwise, I'd have to pay full price just because I write the occasional e-mail concerning money-making activity, and my entire OS install would become unlicensed upon graduation.
Can anyone correct me?
(Not that this is really a legal issue, except where extra terms provided after exchange of consideration are considered legally binding, or where I have missed some smallprint provided to me before sale. But it's interesting to know what Apple would prefer.)