SCOTUS: Tinker v. Des Moines (1969)
Holding: Students do not leave their rights at the schoolhouse door.
To protest the Vietnam War, Mary Beth Tinker and her brother wore black armbands to school. Fearing a disruption, the administration prohibited wearing such armbands. The Tinkers were removed from school when they failed to comply, but the Supreme Court ruled that their actions were protected by the First Amendment.
--And, by not hearing a case, said that 24/7 policies are over-broad:
Supreme Court Refuses to Hear '24/7' Policy Case:
The state Supreme Court has declined to hear a case involving the Ramapo Indian Hills School Board’s appeal of a ruling that struck down a policy that would bar students from participating in sports and extracurricular activities for off-campus misconduct.
The Supreme Court’s denial of certification on Jan. 16 means that the earlier ruling, entered last year by the appellate court, is final. In that ruling, the appellate court found the district’s policy to be so “overbroad” that students could conceivably be disciplined for minor off-campus infractions such as littering.
The case arose when the parents of a high school senior brought a legal challenge to the so-called "24-7" policy, claiming it violated state regulations and provisions of the state constitution.