There are a few Edmodo app that are FREE and worth trying.
eduClipperAllows you to clip items from the web, upload your own work, or find and re-clip content from others to customize and maximize your learning. You can create unlimited boards that you can share with others.
eduClipper allows you to create and manage your classes, create differentiated learning groups, provide students with assignments, provide dynamic feedback and create portfolios.
CodeMonkey
An app that allows students to learn basic coding concepts. The app presents students with a series of challenges in which they must help the monkey reach the bananas. Students must correctly program the monkey to reach the food.
A tool that will allow you to create online seating charts, behavior charts and reports. Through the online seating chart you can take attendance, and record behavior. A nice feature is that you can upload student pictures into the seating charts. Plus. any information entered can be shared with parents using a special login.