There are many iPad accessories. Below are some common iPad accessories
iPad case's are a must have item in the hands of students. An iPad case can significanty reduce damage to iPads. Although expensive they are still a third of the price to replace a broken iPad screen.
iPad video out adapter is an option some might want to take advantage of? With the Video-out adapter the iPad can be plugged into a projection device to "mirror" the iPad screen. If your interested in being cable free while projecting the ipad screen look into the Apple TV & AirPlay.