Installed in the beginning of the school year, a new app was added to the AppleTVs on campus called "Trailers". Although this app is meant for use with iMove on a Mac, it has been modified to take advantage of a "hack" that will allow us to bypass the number of user restrictions on the "Computer" app (which connects to our local iTunes server that houses all of our movies, music and pictures.)
When you launch the Trailers app (everything should already be setup on your AppleTV), you'll have access to the school's entire library of music, movies and pictures as before but with even more granular capabilities to make searching for media easier.
Simply launch the app, select the "shared library" then go to either movies, music or pictures.