There was an all-girl team (private girls school) at SVR last year, and one of their mentors and I inspected there, but I can not for the life of me remember the team name/number.
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The team is from St Francis High School, 692.
The FemBots
From what I have seen, I think all-girl teams are more common then all-boy teams. Well, teams from uni-sex schools, there are more from all-girl schools then all-boy schools. I know my team has a fair mix of male-females.
Wetzel