CapnHook-
In a TX High School you would NEVER get L5Y done.
MTVMANN-
From someone who did mainly RnH in High School (Working being the exception), it's not a challenge acting wise. Just remember, they are in High School, they are "training" or doing it for fun.
If you are worried about the talent pool, wait to announce it until you get in the classroom a week or two. Be prepared to have to take something less well known though, on the off-chance someone in the district decides to do it.
I'll also echo Working as an EASY show to do. Mostly monologues, so you can send kids off with an ASM/SM/AD, build a unit set that rotates, maybe a wagon or two, and the costumes/lighting are a breeze. And, you only need piano accompaniment, AND you're set. No dancing either. The monologues give the kids a chance to really show their stuff, and you don't have to worry about someone forgetting major amounts of blocking. Plus, with TX's No Pass-No Play, it's easy to just remove a monologue versus re-casting. (That's how we went from a full cast to 25)
http://www.youtube.com/huskcharmer