There is a lot of debate about what can or cannot be taught in school. I personally liked to challenge teachers while at school. Evil me. However, some schools are actively trying to break the constitution when it comes to religion in school.
Oklahoma's State Superintendent Ryan Walters issued a directive requiring schools to incorporate the Bible, specifically the King James Bible, into classroom lessons. Usually, the Satanists would sue for the same rights (to teach the Christians a lesson in equanimity) but they are slow to act this time. North Dakota is about to make it compulsory for schools to teach intelligent design in science classes. There is no evidence to prove intelligent design scientific, so science teachers would be forced to lie.
In politics or religion, there will be several sides to every argument and shouting or threatening weakens any argument. Perhaps setting up formal debates to take up differing opinions and argue them with facts would help develop critical thinking. However, this would be unusual in a strictly Christian school I suppose, where disagreement would be anathema to the Christians.