I've flown Young Eagles in my RV-4. I haven't read the info too closely but the EAA does provide some liability protection. However, if a lawyer can write it, another lawyer can find a way around it.

I can't give you much advice in that arena, sorry.
I have a friend who built and now flys an RV-8 who is coincidentally also a HS teacher and he flies YE's as well. I hope you don't let liability concerns put you off giving a kid the ride of a lifetime. It's been very rewarding for me. As a teacher you would probably find it much more so.