I'm an undergrad business student and used it for note taking only in class, but ended up selling my iPad. Once you've used a laptop in class, there's no comparision. Sure you can do 99% of the things you need to do for school, but it was not easy, takes a hell of a lot longer, and not practical. Even with a hardware keyboard, it just took longer to move my finger all over the screen and try to do precise actions such as double tapping a sentence, adding equations, etc.
I'll say this, if I couldn't afford a laptop, I would try to find one of those Hackitosh-able Dell Mini's and install OS X on it (I won't go back to Windows). Use the iPad for fun and as a consumption device and you'll love it.