Free Speech: Dress Code Violation?

In Waxahachie, TX a Texas High School sophomore named Pete Palmer was sent home for violating the school district's dress code. His violation: wearing a John Edwards for president 2008 t-shirt. The school stands behind their decision by arguing that no t-shirt's are allowed unless they pertain to a school organization, club, or sport or are from a college or university. Under these laws, Palmer was in violation. However, the school board may be dealing with more than the media because Palmer's parents are considering filing a lawsuit against the district, and I can't blame them. Where is the line drawn between violating a student's rights and mainting order in the school environment? American's have earned the right to free speech and while I understand some things should be monitored and restricted at school, I think this crosses the line. Palmer in no way disturbed any of his classmates, drew attention to himself, or acted inappropriately. He wore a presidential campaign t-shirt! I went to a public high school and I am very aware of the dress code policies and I hated most of them as a student, but I did understand where the concern was. But this is ridiculous! At some point, school's are going to be like prisons where everyone wears a solid color jumpsuit so that no one is offended or ridiculed for having opinions or concern for what is going on in our world. Everyone in America is protected under the First Amendment and that is the argument Palmer's father is making in support of his son. It will be interesting to see how the school board maintains their reputation with all of the scrutiny and controversy that is resulting from the media's involvement.