One resource that I have been experimenting with lately is Zondle.
Zondle is a tool that allows you to create customized digital games to assess your classroom content. You can input any questions that you'd like and then select a game from one of Zondle's several game formats.
For a quick, easy to start topic, I just dug up a couple of old worksheets from our science unit and added the questions right into the topic screen. You could definitely make this more elaborate, but I just wanted something quick and easy to try it out.
In addition to creating your own content, you can determine if you want the students to play the games individually or if you would like them to participate in a team mode activity. Through secure student accounts- which you can create easily through an excel spreadsheet- Zondle also tracks data about student use and performance in their gradebook feature.
For other great end of the year review activities, be sure to check out my post about end of the school year review activities!