I am not sure when teaching simple facts and skills ends and teaching morality starts. Is the teaching of listening and evaluating claims in an objective manner teaching of morality?
Let's assume a teacher is imposing their beliefs on the class that one should regard all people, regardless of race, national origin, sexual orientation, disability or religious affiliation, as equal. Is that teaching morality? Let's say a family teaches their child that Whites or Blacks are superior, and the teacher teaches they are equal. Is that teaching undermining the parent's rights to teach their children what they believe is true?
Continuing our scenario, assume a teacher puts forth that all people are born equal because the Declaration of Independence says so. Is the teaching of the Declaration of Independence teaching morality? It sure seems like a moralistic statement to me.
Sure, people will argue that sexual orientation and religion are choices. But does this make them less equal as people?