not exactly my expertise, but here goes...
Justin,
Normally Disney really shouldn't have too much to say about this because it is free advertising... if a kid watches, let's say... Atlantis, in school when maybe they didn't get to see it in a theatre, likes it, then goes home and nags a parent until they buy the kid the video/DVD. They would have just made a sale to someone that otherwise might have never even watched the movie otherwise. On the other hand, people are showing it to large groups. I would think that as long as the school is not charging money to watch the video, there isn't anything they can do.