I have been familiar with the iPod touch and iPad. I am able to add and delete apps as well as manage my iTunes account.
Classroom management of devices is crucial. Teachers need to have a specific policy and routine as to how and when they are used and returned. We had several instances last year of devices turning up "missing" at the end of the day or week. It's almost impossible for us to investigate, locate and return devices to the teacher. Unfortunately, once they leave the classroom, they are seldom found and returned. Teachers can and should have classroom helpers, but the responsibility ultimately falls on the teacher to be accountable for the devices. Teachers also need to have a plan if and when a substitute is in the classroom for a day or long term assignment.