Girls in my school never caused me problems...Oh and, I wasn't a nerd, and had girls interested in me. Generally had a girl friend too. But they didn't distract me.
That said...I'd be a supporter of same-sex schools...because I know it can be distracting.
Distraction, that's like saying Obama is a mediocre President.
High school classes should be rated NC-17 or worse and that's without the language.