Ima just say this and feel free to come at me with some knowledge, but it's just my opinion: My gay ass went crazy every time I caught even the slightest glimpse of one of my classmates ****/chest/ass in the locker room back in school. Like, I hated PE but looked forward to it for the simple fact that I'd get to see some real live D before and after class.
Of course nothing was ever acted on because of the stigma against gays and such. But what's going to happen when that situation pops up with a bunch of straight kids who have no reason to hide their sexuality and whatnot? Aside from the obvious bullying and embarrassment, I feel like this opens a lot of kids up to sexual harrassment as well.
It could theoretically work with toddlers and kindergarten students. I'm all for educating kids and getting them comfortable with the opposite sex early. But once they hit puberty, I feel like things become much more complicated.