How does the Tinker decision affect your right to wear a T-shirt supporting a cause you believe in?

The Tinker vs. Des Moines Supreme Court case ensures that students have the first amendment right of freedom of speech in school. As long as the expressed speech does not disrupt the educational process, it is protected by the first amendment. Tinker set this precedent when she and her friends wore black armbands with the peace symbol on them to protest the Vietnam War. Since they won this case, students all over the country can wear armbands or t-shirts as a means of protected protest.