Keyboard stops working after ending sleep mode

My school kind of leases computers to all the students, and this year the computers happen to be Macbooks. A lot of them (including mine) seem to have this problem where, every time I bring the computer back from sleep mode, there is a 1 in 10 chance that the keyboard stops working.

Does anyone know why this would happen? It's really annoying. I usually have to restart OSX. Windows XP never does stupid stuff like this.

Have you tried taking to your school about it? It is their laptop maybe they can do something about it.