Are you looking for a simple devotional to do with your family in the weeks leading up to Christmas? Barbara Reaoch's Why Christmas? is a helpful devotional to point your kids to Jesus with colorful illustrations and good discussion questions. I just started reading it with my 3 kids (ages 10, 8, and 4) and all of them really like it. The devotional also comes with Christmas carols that correspond with each of the stories. It's a fun way to end the night before tucking them into bed!
I also recommend Why Easter? by the same author.