Public schools have always had the goal of preparing students to be productive and responsible citizens. Of course part of that process is training them to speak English in public, just as our ancestors did while they were acclimating.
And what about equity? If those Spanish children get to use their language in the playground (which can be a dangerous place if children can't understand the direction of supervisors) why not everyone else? A lawyer for "equal rights" could have a field day with that one!
Sounds pretty close to fascism to me.
I speak with my family and children in Polish (also in public). My children speak Polish among themselves even in school. Are you going to punish us?