You (or others reason this thread) would probably be interested in the most recent Serial podcast, "The Trojan Horse Affair", which centers on the intersection of religion and public schooling in Birmingham. Religious education is apparently technically a requirement in the UK as well (though, in many places, perhaps more observed in the breach). If you're Muslim in Birmingham, your public school is probably teaches approximately as much Islam as St. Barnabas taught me Catholicism.

(It doesn't work out great for Birmingham!)