Some CofE schools are also used as free prep schools for private secondary schools- with the curriculum biased towards preparation for entrance exams, etc


All state schools are subject to OFSTED inspections, SATS testing and the National Curriculum.
So "Private prep schools? " Hardly.
Anyway I thought your objection was to the teaching indoctrination of religion? Not the academic standards.
I think we need to bear in mind term "faith" school covers everything from village C of E First Schools to Jewish schools to extremist Muslim schools in certain of our cities. As such it is an emotive term. Before the blessed Tony Blair gave the go ahead to faith schools of every hue, we had some excellent primary and secondary C of E schools, usually sought after for the quality of the education, the caring environment, the pastoral care and the standards. Many of my DDS' classmates 30+ years ago in their S London church primary school were of Asian parentage, whether recent or second generation immigrants I have no way of knowing. It was a genuinely mixed school -socially too. That was not "medieval", that was not indoctrination, the annual Christingle service or Nativity Play at the parish church in no way segregated or indoctrinated the children. Many of my atheist friends expressed no objection, as most of us, practising Christians or not, enjoy a children's nativity play.
Thanks to Tony Blair's "inclusivity"(?) the baby has now been thrown out with the bath water, but why the tub thumping alarmist accusations of the "dreadful things" that go on, or the nigh-criminal lengths parents will apparently go to?(Also the subject of a long and tedious thread some time ago)
IMHO emotions are being whipped up, , harsh words spoken and well, it sounds a lot like <stirring>