One of the most frequent questions I have been getting about my iPads is "where did you get those cases??" We have been using Trident Kraken cases. They come in a wide variety of fun colors and seem to be easy for students to grip and hold on to. They also have a clear screen protector built in and I have been able to use clorox wipes to keep the germ spreading to a minimum. There have been no iPad catastrophies to date! Check the cases out on Amazon.
Our district woodworker also made me a storage shelf to keep the iPads charged and safe when not in use. The cables go through a small hole in the back of the case and plug into a large surge protector, out of sight. The shelf also keeps the charging cables out of view, as I am told they are hot items that often walk away from classrooms, since they can be used for charging students' iPods.