Mr. Frederick later testified that he designed the banner, using a slogan he had seen on a snowboard, “to be meaningless and funny, in order to get on television.” Ms. Morse found no humor but plenty of meaning in the sign, recognizing “bong hits” as a slang reference to using marijuana. She demanded that he take the banner down. When he refused, she tore it down, ordered him to her office, and gave him a 10-day suspension.

Mr. Fredericks’s ensuing lawsuit and the free-speech court battle that resulted, in which he has prevailed so far, is one that, classically, pits official authority against student dissent. It is the first Supreme Court case to do so directly since the court upheld the right of students to wear black arm bands to school to protest the war in Vietnam, declaring in Tinker v. Des Moines School District that “it can hardly be argued that either students or teachers shed their constitutional rights to freedom of speech or expression at the schoolhouse gate.”

The court followed that 1969 decision with two others during the 1980s that upheld the authority of school officials to ban vulgar or offensive student speech and to control the content of school newspapers. Clearly there is some tension in the court’s student-speech doctrine; what message to extract from the trio of decisions is the basic analytical question in the new case, Morse v. Frederick, No. 06-278. What is most striking is how the two sides line up.

The Bush administration entered the case on the side of the principal and the Juneau School Board, which are both represented by Kenneth W. Starr, the former solicitor general and independent counsel. His law firm, Kirkland & Ellis, is handling the appeal without a fee. Mr. Starr and Edwin S. Kneedler, a deputy solicitor general who will present the government’s view, will share argument time on Monday. The National School Board Association, two school principals’ groups, and several antidrug organizations also filed briefs on the school board’s side.

While it is hardly surprising to find the American Civil Liberties Union and the National Coalition Against Censorship on Mr. Frederick’s side, it is the array of briefs from organizations that litigate and speak on behalf of the religious right that has lifted Morse v. Frederick out of the realm of the ordinary.