The US Supreme Court decides the 1st Amendment prohibition on the legislature applied to schools too, and forbid what was common reference to God, morals, prayer, Christmas or Easter based on a new interpretation that made government hostile to religion, rather than walking together in mutual respect. Religion & its principles were forbidden in public schools. The ACLU enforces it vigilantly with litigation. So teachers have no morale reference point when discussing good and evil. It’s all whatever you want good to be. Without a God based standard it’s might makes right via situational ethics.