But she did agree, she signed the permission paper. If she really opposed their policy, she should have taken her dear child elsewhere for his education. Maybe if she had paddle his behind herself and took him to school, the school wouldn't need to paddle him.
If she signed a paper that specifically says she will allow corporal punishment by school officials while not under threat or duress (as she claims), then she doesn’t have a valid claim.
It remains to be seen whether she can prove duress and/or threats by the school.