If you're a child in the United States, you can't legally vote, drive, hold public office or even see some movies without an adult with you. But that doesn't mean you don't have constitutional rights.
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The Constitutional Rights of the Student
Although children and teens enjoy the same rights as their elders, the Supreme Court has repeatedly limited student rights to free speech and expression in school. The Court has also upheld censorship of school newspapers and suspensions of students for inappropriate language and behavior. Schools have even been allowed to search students' private property without probable cause [source:
FindLaw]. In that particular case, New Jersey v. T.L.O., the Court found that a school's responsibility to educate and protect children trumps student privacy, and allows school authorities more leeway than the police would have outside school [source:
Dorf]. The court ruled on that case in 1985, but student rights have been further restricted since then.