Classroom by Apple (Free)
This is an app created by Apple aimed at making iPad management easier for teachers in the classroom. The app allows teachers to control and monitor other iPads (as long as they meet minimum system requirements) in the classroom. Here are some of the things that the app can control on one or more iPads:
The app relies on both Bluetooth and WiFi connectivity. I have tested it with up to six iPads but apparently the app can handle up to 30. The app is particularly useful for students who may require a lot of support (e.g. kindergarten students) or with older kids who can't regulate themselves. See the tutorial section for information on how to configure it.