LRD - I'm Anglican now, though I started out Church of Scotland so I've seen some different angles. Add in a couple of years of theological college, and a whole lot of new angles from that, and I hope I have a reasonable understanding of it. But yes it is depressing to have to explain even the most basic theological concepts, specially to people who are convinced they know all about it because they've heard some garbled versions along the way. I'm not sure what does get covered in schools, but I think there must be a strange lot of stuff, since so many parents are irritated at how much religion gets into schools, and yet the basic principles of how it works don't seem to be taught.
But then I feel the same about science teaching, where everyone has been taught science at school, but only people who have gone on to specialise in it seem to understand how the scientific method works.
We seem to be raising children who know lots of odd bits and pieces, but have no structure with which to comprehend them.