This link: https://quizlet.com leads you to already created study sets allowing the teacher to introduce and review material in a variety of ways. Students can choose activities that suit their learning style. Examples are: Flashcards, spelling, tests and matching games to name a few. It even includes audio that will read to the students!

Quizlet's mission:

To help students (and their teachers) practice and master whatever they are learning. Quizlet provides engaging, customizable activities with contributions from people everywhere.