It seems that there are a number of concerns here.
If colored hair was taboo, it should have be written in the Code of Conduct. Was your child the only one to have his hair washed? If the school decided to enact a policy about colored hair after the Code of Conduct was printed, was a letter sent home to the parents letting them know that brightly colored hair wasn't allowed in school?
Perhaps the teacher and nurse could be given the benefit of the doubt. Everyone makes mistakes. No one is perfect. The feelings that you have for this teacher is separate from the color of the hair.
Again, was your child singled out? It's hard to believe that no one else in the school came to school with colored hair. If so, how did the students know that it wasn't allowed?
As far as the nurse, that's a toughie. Assuming that she had the best of intentions, a better course of action might have been to let you son go to the boys' bathroom and remove the color himself. Taking off his shirt is a no-no.
What's difficult for educators now is that our schools are often blamed for the ills of society. Low test scores, children who seem to have lost their respect for authority, Columbine. The list is endless.
As far as the saying on the t-shirt, I can honestly see where a school might want students to demonstrate respect. Again, this should be written in the Code of Conduct.
If the school district feels that something that a child wears is distracts others or is rude, I don't have a problem with that. Again, this must be made clear at the beginning of the school year.
As long as my child was able to wear dry clothing, I would be happy if the school changed her wet clothing. I think that it would be more of an embarrassment to her to be soaked in urine all day. Again, some schools let parents send in extra clothing, some don't. There are times when my daughter has been sent home in what may be construed as boy's clothing. Maybe it's just me, but I'm happy that the school tried to make her feel comfortable.
Not much bothers me because I know how difficult it can be to work in a school system. There was only one time when I went to a member of the School Board; but that was after I followed the chain of command and didn't get any assistance.
All the best to everyone,
Suzy