I was thinking...
So many films and television shows seam to glorify cattiness between females--of any age. Camaraderie just doesn't seem to be acceptable.
And, regarding the transition from child to young adult, there doesn't seem to be any real cultural guidance to replace childhood play with acceptable tween/teen activities. Other than sports (and nearly everyone knows my opinion about that!), there seem to be few options for individuals to develop and learn to like themselves without worrying about what their peers think.
I'm so thankful I was involved in ballet at that age. Serious physical activity, discipline, opportunity to learn things not taught at school and some really fun times. And, yes, some cattiness. Just can't seem to get away from it.