As they get older the previous rituals will seem childish. They will enjoy a newer rock song about Jesus' coming into our violent world. Children also like to move around. Expecting them to sit through a long service, sermons without illustrations, and interminable prayers, is a sure way to put them off church for the next thirty years. Some of them might eventually come back when they have ceased to be childlike and are bored enough to join in our geriatric activities.
Children love stories.
And strangely enough when stories are told in a sermon that is what the adults remember. Which is why instead of sermons Jesus told parables. Heavy theology and the detailed exegesis of Romans and Hebrews and the Book of Revelation has a place, but it should be at a separate time from the main service for those adults who are ready for that. But that does not mean that children are not keen to learn. Most of a lifetime of learning takes place in the first seven years of our life.