Easy Notecards is a great tool for both students and teachers.
What sets Easy Notecards apart from the other notecard/flashcard sites out there is it allows you to create notecards for a specific book. Easy Notecards even goes one step further by allowing you to enter the chapter(s) the notecards are for. This makes it so much easier to find what you are looking for since Easy Notecards organizes notecards by chapters within a book. And since each notecard set has a Helpfulness Rating you won't waste time studying notecards that aren't very good.