From FIRE's letter sent yesterday to the Superintendent of Harrison School District Two in Colorado; I generally trust FIRE's factual accounts in such matters, and I think its legal analysis here is spot on:
The Foundation for Individual Rights and Expression (FIRE), a nonpartisan nonprofit dedicated to defending freedom of speech, is concerned by The Vanguard School's removal of student Jaiden Rodriguez from class for displaying Gadsden flag and Firearms Policy Coalition patches on his backpack. As over fifty years of Supreme Court precedent makes clear, the First Amendment protects Jaiden's silent, non-disruptive expression of his views at school. FIRE calls on Harrison School District Two and The Vanguard School to confirm they will permit Jaiden to attend school with the patches on his backpack without facing discipline or removal, and for the district to revise its unconstitutionally overbroad dress code.
The Vanguard School Removes Jaiden from Class for Displaying Gadsden Flag and Firearms Policy Coalition Patches on His Backpack
Jaiden Rodriguez is a seventh-grade student enrolled at The Vanguard School, a tuition-free public charter school within Harrison School District Two. {The narrative in this letter reflects our understanding of the pertinent facts, but we appreciate you may have more information and invite you to share it with us.} For two years, Jaiden has displayed various patches on his backpack without incident, including one depicting the Gadsden flag, which shows a coiled rattlesnake above the words "DONT TREAD ON ME." {The flag traditionally lacks an apostrophe in the word "don't." [Now that's a reason for banning it! -EV]} The flag was designed during the Revolutionary War and symbolized the American colonies' united resistance against the British monarchy.
Jaiden has also long displayed a Firearms Policy Coalition ("FPC") patch, which includes an image of a rifle. FPC is a nonprofit organization whose "efforts are focused on the right to keep and bear arms and adjacent issues including freedom of speech, due process, unlawful searches and seizures, separation of powers, asset forfeitures, privacy, encryption, and limited government."