I like Dude's advice. Definitely worth trying to see if your daughter can reframe her perspective of the classroom.
Unfortunately, my dd8, has been in similarly unbalanced classrooms since 1st grade. In a class of 18, she was one of only 3 girls in first and second grade. Now in 3rd, there are 7 girls and 20 boys, so better, but still a boys dynamic.
For some reason, my dd often gets grouped with all-boy groups. Her reading group left her in tears because the boys never listened, never let her talk, were bossy and took control. She doesn't want to talk over them, so she just gave up. When she finally told me about it, I emailed the teacher, but the book was finished by then. The teacher promised she would make sure the girls have a friend in groups from now on.
But the teacher also tries to put rowdy boys next to my dd to calm them down. This, also, makes my dd frustrated and upset. After a discussion with the teacher, my dd is now next to a quiet boy, so that's an improvement.
I think I would try Dude's suggestions, but honestly, my daughter doesn't like playing with boys and even though she's madly in love with her brothers, she doesn't like boys her own age. She thinks they're literally crazy. So I'm quite sure I would have to remove her from an all-boy classroom.
PS-- I'm not boy-bashing! I have two wonderful boys, but I know boy energy is often different than girl energy. I'm surprised my tom boyish girl doesn't gravitate toward boys, but she doesn't.