In my opinion, the recent story of the Muscle Shoals High School student who had "disruptive" red hair being sent home and told to dial it down a bit is part of what seems to be an increased sense of self-importance and control that schools are assuming over the students' and teachers' lives. I am so sympathetic with the unfortunate, put-upon girl.
In recent years, some public schools are even going in for school uniforms. Now I had to wear one while going to a Catholic school; and it sucked. So did having to polish the brass buckle of the khaki web belt. I prefer jeans; as a matter of fact, I wish I could have worn them while teaching on the university level!
The local Florence, Alabama schools had a dress code which included a prohibition on shirts with legible writing involving off-color or beer ads and hoodies, even though the message was nonthreatening and inoffensive. As a matter of fact, some students were sent home for wearing t-shirts praising the head of the school board! Geesh! Humor-challenged administrators!
Another example comes from Alaska in the Frederick v. Morse case. Some high school students held up a sign at an off-campus event involving the passing of the Olympic torch bearing the message "Bong Hits 4 Jesus" and their school disciplined them by suspending them for ten days! The school did so despite the fact that the parade in question was an ordinary public event and not one sponsored by the school. Unlike an earlier student rights case, the Tinker v. Des Moines case, the Supremes backtracked on student rights. Apparently, there was a built-in judgment that quality of the content makes a difference. Okay, protesting a war is serious stuff, unlike a satirical or humorous message that seems silly. But isn't that beside the point?
Teachers' rights as citizens have been also abridged by their employees (the schools). For example, a teacher was summarily fired because she posed for an "Eye Candy" modeling magazine [as it styled itself]; and another for serving as a bikini crew member on a charter vessel during weekends. Would some rigid principal also fire one for discovering her arete in a roller derby or as a stand-up comedian?
These sorts of thing can stack up in the long run. Singly, they might seem small-scale; but together they can result in an augmentation of school system authority at the expense of students and teachers. Do we really want school boards or principals to have such dictatorial authority? I've never seen academic administrators who could manage as philosopher-kings.
There's another aspect. As a former low-level college administrator (an academic department chair), I have learned that one should avoid looking dumb, petty, or silly. Sometimes you're called on to act that way by your bosses; but then it just sucks all over. Still, turning a blind eye and being an absent-minded professor can be an adaptive strategy.