[longtermmemmory]

Be specific in your letter. Which school is this, which teacher? Did you complain to the principle and were your concerns disregarded?

You may want to couch this as censorship. "The school at X refuses to show any non-liberal perspectives on gun control. Instead they will only allow the dubious 'mockumentary' made by an admitted maxist. When I contacted my child's teacher and principle, I was advised that the 'mockumentary' was the only political opinion allowed taught to children."

[countrydummy]

got ya! Thanks for the advice!