Outside of schools that are faith based, schools are not suppose to teach religion outside of religious classes ( if they have them).
IF, and that is a big IF, the teacher said that, you need to find out the context of the conversation.
I doubt it was part of teaching for a 6 year old ( grade 1, yes?).
My kids go to a Catholic school ( it was the closest to us and it is small and a great teacher to student ratio).
They teach about God of course in religion class, they pray of course, say the golden rule everyday, zero tolerance policy for bullying and violence in school AND they teach evolution in science class.