Just a quick note about automatic updates in iOS 7. Students can turn automatic updates on by going to Settings –> iTunes & App Store and then scrolling down to Automatic Downloads on the right. Turn it on for Apps and they will download automatically from then on.
This works even if you have turned off the App Store using restrictions! This way, apps will update without the teacher having to turn off the restrictions every time!
It also saves you from having to reenter passwords so often.