This article on homeschooling pretty much hits the nail on the head. It reminds me of reading one of Doug Wilsons' books on homeschooling/classical education. To paraphrase, he said that public/state-run schools are mandated by law to tell our kids that God is completely separate from the classroom, and what Christian parents should be instilling is that God is the Great Designer behind every single thing that they learn. (edit: I should add that DW does not contend that one has to homeschool in order for their children to learn this. He does say, though, that as parents we are responsible for what our children learn even if they are in a public school).
From the article:
"Probably the most significant benefit of home schooling, though, is one I didn't mention in my previous column. Home schooling puts parents back in control of their children's education. That's not to knock the legions of dedicated public school teachers who do their best to educate kids. But when someone else is educating your child, it's that person's philosophy of education and his or her ideas about what's important -- not yours -- that govern what's taught." (emphasis mine)
I'll just stop typing now before I really get up on a soapbox.