I'm not sure how things are in the US, but I do know that in the UK we have the Boy Scouts and the Girl Guides, and they both allow members of both sexes. But you do tend to get a lot more girl scouts than you do boy guides.
Here in Portugal we just have the Scouts, and they're unisex. Well, actually we have two Scout groups, the Catholic and the secular, but they're both unisex.
