When do you teach children about God?

My parents are free thinkers, they bought a children's Bible for me when I was 6-8, and they also explained about Taoism and Buddhism to me. They were quite clear they don't know the answer and it's fine for me to follow my beliefs. I'd been thinking for myself since and even now try to learn more from believer friends; although I respect their beliefs and think they are doing good for believers and society (not a blanket statement for established religions, there are some institutions whose business model/preaching I think are simply destructive and selfish) I'm still quite solidly in the atheist camp.