Here are a list of precedents for the Tinker vs. Des Moines case.
-Waugh v. Mississippi University (1915): the Court ruled that the states control institutions they established and that the state can prohibit things it believes distracts from the purpose which the state desired to exist.
-Meyer v. Nebraska (1923): the Court ruled that laws which interfered with the liberty of teacher, student, and parent were unconstitutional.
-Cox v. Louisiana (1965): the Supreme Court ruled that the rights of free speech and assembly do not mean that anyone with opinions or beliefs to express may address a group at any public place and at any time.
-Hammond v. South Carolina State College (1967): it was ruled that people in public schools are protected by constitutional rights.