You're twisting it, and no you don't. You were no more aware of the rulings before I presented them than you are now.
Tinker vs. Des Moines says administrators in schools cannot punish students free speech if it doesn't disrupt the educational environment. So, what about that pro-life display disrupted that school's educational environment? Care to elaborate?
Tinker said that the arm bands were expressing a Political View and not disruptive to educational environment, which the authorities are charged with maintaining. Had it been a Nazi armband they would have lost, as that would have been considered to be disruptive by a reasonable person.
The Pro-life display, with graphic pictures of aborted fetuses in the lunchroom, would be an obvious one to crack down on. They did not stop an abortion debate in a debate class, although they certainly could have, they stopped what they felt was disruptive to, in this case, kids eating lunch. They could just have easily stopped other forms or protected speech outside the environment as well such as Preaching, Stripping, and Singing God Bless America. They are charged with keeping the order and the courts usually give them the benefit of the doubt even when they error.
A time and a place my young friends, a time and a place.