It applies to the parents. There are many things concerning the teaching of children which parents need to be reminded. Narrative history of America with original words of the Founding Fathers used in context of the story. Parent freedom of choice for what their own children will learn. Method and content of instruction are vitally important to parents.
Many options exist.
Parents have rights endowed by their Creator to know those options and the consequences of those choices. A right government exists only by the consent of the governed. Consent exists only when the parent knows the whole story and agrees to it. You are the parent. It is not censorship for parents to direct the learning of their children.