Why does tinker v. des moines remain an important precedent setting case

Tinker v. Des Moines Independent Community School District, 393 U.S. 503 (1969), was a landmark decision by the United States Supreme Court that defined the constitutional rights of students in U.S. public schools. The Tinker test  is still used by courts today to determine whether a school's disciplinary actions violate students' First Amendment rights.