Of course, teaching religion in schools (public or private) should ALWAYS mean teaching "about" religion. Preaching, fostering a particular faith is not a function of a school, but of a church or other strictly religious organization.
EZ, I understand very well what you mean - I live in the Bible Belt of Bible Belts (east-central Mississippi). That really is a horrible problem and I don't know how to fix it. I think the STATE, the government must simply close schools where kids are taught literal 6-day creation in science classes, etc. Parents' will should not be taken into consideration at all, IMHO. That's one element of governmental dictatorship that I would support. After all, the US government will close down a school that teaches its kids that the earth is flat or that all Jews are evil monsters. Pretty much by the same token, it should not give accreditation to schools that substitute narrow-minded literalistic interpretation of certain religious texts for education.
Richard