I noted the school in question was “Friends School” in Philadelphia. A typical modernist, expensive, elitist puppy mill that decades ago abandoned its mainline religious/protestant roots.
I took my oldest daughter to a similar school in our city for an open-house, as she was preparing to enter high school. I asked one of the trustees on hand if there was any particular religious ethos that guided the school, particularly in their many courses about “social justice” or “rights.”
He sniggered like I was some kind of caveman and said “no, no - none of that stuff”