Finally, courts started coming around to the idea that reasonable limits on student attire were appropriate and permissible, and they should come around to that idea about ALL kinds of speech as well.
The truth of the matter is that before politically directed interference by the ACLU against public schools, those schools could always limit what they considered vulgar or inappropriate clothing, language, expression, and even attitudes that were over the top.
The leftist crowd led by extremist groups like the ACLU began to use parents and students to sue schools and school boards that did not give up on 200 years of American culture and begin to let any vulgar dressed, foul-mouthed, students spread the ACLU's anti-God political revolution to reinvent America through the government monopoly of education.
The ACLU types needed to use people for progressive lawsuits so that the leftist courts could get involved and 'walla', the leftwing revision of the public schools and the law was in place.
Students who served the left's politics, subversive intents, and anti-God revolution we not limited by the ACLU in any way. They never come out against speech that advances their leftist cause, they only sue those who stand with 200 years of American culture and morality which the ACLU fights with all its energy.
The ACLU types only began to step in if a conservative religious person spoke up with a forcefullness approaching that of the decades of anti-Christian vulgarity and leftwing politics that fights against the ACLU humanist utopia.
Clarification: The ACLU types only begin to step in if a conservative religious person speaks up with words that run contrary to the ACLU and fights against the ACLU humanist utopia.