The features of Quizlet also make it exciting in addition to the amount of pre-made material. For example, a teacher can set up a site for an unlimited number of classes and use features such as voice recording and image uploading with the paid account. Imagine posting a homework assignment with voice instructions and with 20 questions that are already created, and receiving the results in a tidy report without even having to scan a single scan tron! A link to this fantastic tool can be found here.
An excellent screencast video is below and can also be found on YouTube.