This might be a duplicate if the first one is restored:
The attached are 20 pp from a book by a wise and thoughtful secular mom on how to make religious holidays less stressful for our children. She has thought long and hard about this subject and has some very keen insights and suggestions on how we can better cope and keep our children attached to their community but not indoctrinated with the baloney.
My approach (children and grand children) has always been low key. Deal with religion by explaining its irrational nature in general conversation. But I've never been hardball about holidays because we (including the kids) understand it's just an excuse to play a game, not some imaginary god's command.
A Jewish or Muslim child doesn't dare celebrate Christmas because his jealous god will be pissed. An atheist has no such worries.