> Boys need to learn how to be men. Just like girls need to learn how to be women.

Do they? That suggests not only that there's one right way to be a man/woman, and that you'll need to learn it from your peers and not just your parents.

I do think there's a point to gender-segregated spaces for kids, but that is because the social dynamics are different. There are some ways a boy can relax when there's only other boys around, and same for girls, and that's probably good for mental health. But you're still a man/woman even if you didn't get that chance and went through your whole childhood worrying what the opposite sex thought of you.