Seems like a silly lawsuit to me.

These kids can't speak Spanish at home, after school and on weekends????

I can understand why the rule's in place, can you imagine being a teacher in a school where the kids spoke a different language in their break, for all you know they could be planning to break into the science lab, or steal the teachers car, or whatever else it is kids get up to these days.

That said where I went to school that sort of stuff was plotted in English anyway, the teachers just never seemed to listen.