Shouldn't schools focus on teaching the First Amendment rather than trampling all over it?

Via the Las Vegas Review-Journal: 

While the U.S. Supreme Court has allowed public schools to limit the rights of students in some instances, it has also ruled that kids don’t shed their constitutional freedoms when they walk onto campus.

That’s why a Reno middle-school student is on solid ground in his lawsuit alleging the Washoe County School District violated his First Amendment rights by telling him to cover up a pro-gun T-shirt...

The district maintains that the shirt violated its dress code, which prohibits clothing with “sexual overtones, or anything that promotes firearms, alcohol, drugs, tobacco, gang membership or violence.”

But while schools may indeed restrict student attire that is obscene or disruptive, sartorial regulatory schemes that discriminate based on the message conveyed clearly violate the Bill of Rights. Ask yourself: Would the district have done the same to a student sporting an anti-NRA armband in support of recent student walkouts over gun violence? The answer is obvious.

Read more here.