The parents used very poor judgement in sending their daughter to school with a hairstyle that was not allowed, kempt or not. The rules were written and presumably agreed to by the parents before admission.
This is a charter school- attendance here is not mandatory for this girl. Whether or not you think particular hairstyles should be part of the dresscode, this special little snowflake and her parents knew before hand what was or was not considered acceptable at this school.
The cries of “racissst!” are certainly misapplied since the school administration share ethnicity with this child and her family- no evil white people to be blamed here.