This may be of interest for college students wanting to save some cash while using their iPad.
Amazon has an offer where you can save up to 80% off retail book purchases by renting the ebook versions. According to the site, you can rent them from 30-360 days, plus add additional days on and have the option of purchasing.
I don’t know if you could do this with all of your classes but I imagine that this would work great with at least some of them.
It even says that you can “Access your notes and highlights anytime, even after the rental expires, at kindle.amazon.com.”
For more info, check out the below link.