I've been surprised at the number of people on this forum who think the Constitution doesn't protect 'minors'. Glad to see someone knows better.
Conversely, there's the Hazelwood decision, which gave school officials broad powers to censor school newspapers. Anyone who's attended a public school in the last 20 years knows that free speech rights are heavily regulated when you cross the threshold.
http://teacher.scholastic.com/researchtools/articlearchives/civics/usgovt/judic/hazstupr.htm
It does not follow, however, that simply because the use of an offensive form of expression may not be prohibited to adults making what the speaker considers a political point, the same latitude must be permitted to children in a public school. In New Jersey v. T.L.O., we reaffirmed that the constitutional rights of students in public school are not automatically coextensive with the rights of adults in other settings.
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Nothing in the Constitution prohibits the states from insisting that certain modes of expression are inappropriate and subject to sanctions. The inculcation of these values is truly the "work of the schools." The determination of what manner of speech in the classroom or in school assembly is inappropriate properly rests with the school board.
- Bethel School Dist. No. 403 v. Fraser, 478 U.S. 675 (1986)
Tinker said from the outset that the schools have a vested interest in controlling "disruptive" speech. Who determines what's "disruptive"? Well, according to Bethel and Hazelwood, the school itself determines what's "disruptive".
That is an interesting issue. Minors are a special class that are subject to a more elastic interpretation of The Constitution than adults. For example, the 4th Amendment has been pretty much tossed out on school grounds (and rightly so). The 1st amendment is subject to constant re-interpretation (as in the instant case). School uniforms have been found to be constitutional.
What is important is that if there are free speech issues that both sides of the argument be heard. It is patently wrong to allow pro-gay agenda "speech" without allowing the opposite side equal time.