[Hatteras]

"He told them not to look. They looked."

Kids just don't listen these days...

[Vigilanteman]

It is very possible that the school has a policy on never leaving the classroom unsupervised for any reason. Since the guy made an effort to conceal his action, I really don't think they can make an exposure charge stick.

There are some places (even in elementary schools) where the kids will tear the place apart even in the three minutes or so that it takes to dash down the hall for a quick leak.

Personally, I think the best way to handle this is to thank the guy for his service, maybe even give him an appropriate retirement gift and find another substitute teacher in the future.