Most adult worship services are geared toward exactly that, adults.
Children are obviously different and interested in different things.
When their is a worship service geared toward the children, it makes them feel involved, because they are involved. Our lifestyles today are such that children are as busy as adults. In order to hold a childs interest in what your teaching, you must gear the lesson to them. Such as puppets, ventriloquism, gospel illusions, songs have actions that involve the kids, and many other things geared toward children. In my opinion, if you don't keep the kids interested, you'll never reach them.