We're not religious (in fact, I'm Hindu, DH is Christian, but neither of us practice our religions), and our DD goes to a Catholic preschool. They say grace before eating and have chapel one day a week where they learn some stories and songs but to my 4 year old it's just stories and songs. She does yell at me if I go "Jesus!" about something bad, though, which is cute! It's totally fine and I don't think very many of the families at our preschool are religious either, from what I can tell.