I guess I don't understand how the central purpose of the school is evil, based on the things you mentioned in your opening comments. Yes, it sounds like it has some views expressed on the walls that are questionable but, for example, having a misinformed view on global warming evidence of an evil central purpose. I don't know - I don't know the school or those involved - you do.
Those things (global warming, mindless tolerance, etc.) are but symptoms of the central evil of the institution. I'm not speaking of just one school that I know particular things about - this is a broad brush against all of them.
Their central goal: educating children while specifically removing our Lord and His Word from the exercise. That's evil, especially when done toward the children of believers, where they will inevitably (regardless of their perceived kindness) lead children into false ideas, feelings and perspectives. It is not possible to educate children while ignoring or denying Christ and not lead them astray in some way. And Christ tells us these folks would be better off with a millstone about their neck at the bottom of the ocean. I don't quite understand why we would voluntarily send our children to an institution like that.