There are some pretty decent flatbed scanners with very small edges around the glass. This doesn't damage the book so you can sell it back at the end of the term. Most flatbed scanners are easily up to the task. All you really need is about 300dpi...but the faster it can scan the better. It gets really old, really fast sitting there waiting between pages.
Here is a recent review of some scanners:
http://flatbed-scanner-review.toptenreviews.com/
Where you want to invest your money is a good OCR software. That will save you a bunch of time and lots of headaches. I recommend ABBYY Finereader (I think version 11 is the latest?)
Good luck!