Do Students Shed Their First Amendment Rights at the School House Gate?

I'm finishing up my senior paper for my First Amendment Seminar class (finally!). Before you can graduate, you have to take a seminar class on some area of law that interests you. I took the First Amendment Seminar more for the professor who was teaching it. He's an excellent teacher, who is incredibly knowledgeable on the Constitution. He was my Constitutional Law teacher my first year, and I really enjoyed his classes (though he scared the crap out of me - he'd randomly call on people to lead class discussion, and if you weren't prepared, he didn't move on - he'd stick with you, prodding you throughout the class).

Part of the seminar class requires writing a law review-type article on a more narrow topic of law that stems from the broader course subject. I'm writing on public school students and their freedom of speech. It's a pretty relevant topic, because this past summer, the Supreme Court just handed down a decision in Morse v. Frederick, only their fourth-ever case dealing with student speech rights at school. Maybe you heard about it? It all centered around this sign: "BONG HiTS 4 JESUS." A group of students in Juneau, Alaska attended the Olympic torch rally as it came through their town and held this banner to attract the attention of the television cameras. They had been given permission (along with the rest of the school) to attend the rally during school hours as a school-sponsored outing (sort of). The high school principal quickly ordered the students to put the banner down, and all but one student did so. Joe Frederick kept holding the banner, asserting his First Amendment rights to speak at school. He was suspended for it.

Okay, so the message is a bit...idiotic? Not at all eloquent, complete nonsense, and not a very important message to try to assert your First Amendment rights on, but was he right? Did he have a right to hold that banner? The Supreme Court didn't think so. They found in favor of the school principal, finding that she "reasonably interpreted the sign to be a promotion of illegal drug use."

Now, maybe you find the sign offensive, or at least really stupid and embarrassing to have your town identified with on national television. But, is it really promoting illegal drug use? I don't know. Frederick said it was a nonsense sign, meant to evoke a strong reaction and attract attention, but not meant to encourage drug use. And would any student read this sign and be likely to try drugs as a result? And what does this do for student speech? If now it's permissible for a school to suspend a student for a statement like this one that arguably means nothing, but references a drug phrase, what else is permissible? What about honest discourse on the legalization of marijuana? Suspendable conversation?

Or maybe this is necessary to control the classroom environment and ensure that students aren't exposed to disturbing or offensive ideas. What do you think?