The school folks really can't hide behind that kind of argument anymore. In fact, the Momma probably ought to show up at the school tomorrow morning (after writing out a child endangerment complaint at the nearest station house), along with the cops, and haul these yahoos out of there before they get a chance to mess with more children.
It's literally amazing to watch how fast cops will gravitate to the "other side" of a question once somebody has filed a formal complaint.
Seriously, don't you think there are attorneys calling her all day to try to line them up as clients? Follow the money