Assuming that things are as the article describes (which I feel is unlikely, as the article is written rather poorly and seems designed to incite outrage rather than objectively report the facts), this is an issue best addressed by the school admin and the parents of children at the school. The parents pay a lot of money (a LOT of money - $25K a year for nursery, going up to $43,900 for the last two years of high school) for their kids to attend this school, and you can be sure that if the actual instruction is out of line with the parents' values, it will be shut down ASAP.

If, on the other hand, the article is distorting the facts, and the parents are happy with the content of the instruction, it really isn't somethat that you or I have any say in. For better or for worse, PA allows private schools, private tutors, and home educators a lot of leeway in curriculum content, so long as certain basic subjects are taught. And that's the way it should be.