Hi Adam,
You don’t really need to have students login/logout of the tablets, as they will be using them to test their apps. You should download the MIT AI2 Companion app onto the tablet, and you can just set up one google account to be used for all your tablets. Then, each class using the tablets can just use the MIT AI2 Companion app that’s loaded onto the tablet without affecting any work from previous students. The only thing they should make sure they do is close the app at the end of class.
All development is done on the computer. By downloading onto the companion app, you’re just downloading code that gets interpreted on the tablet, so there is nothing permanent there.
Hope that helps.
Karen