Looks to me like kids were being kids and cutting her hair because it was outside the norm. Looks sort of like a blond afro.
Seems possible the teacher didn't know the parents had it cut in an asymmetric style and was trying to even it out in a well meaning, but poor judgement kind of way. I'd be curious to hear the logic before jumping to conclusions. I wouldn't be surprised of the parents' outrage is becoming unnecessary trauma for the little girl. I'd be curious how she took it. Very possible she's better off out of that school.