Most of the congregations I encounter in ministry have high average ages, and that average won't go down in the near future. This demographic reality produces an emotional response in congregations.
In conversation gatherings of these older church-attending adults, I hear about a longing to see children in church. These longing congregations vary in their degree of connection with children, with a conglomeration of activities. Some congregations host a preschool or childcare facility. Some congregations provide an after-school program, or give meeting space to Boy Scouts or Girl Scouts. Some congregations host a vacation Bible school, or support a teenage youth group. For all of the hospitality and community connection a congregation makes, these programmatic connections don't mean as much to congregations as youth attending worship. Problematically, this is where the exploration of the dearth of young people ends, and a section of the body of Christ in North America continues to drain its vitality. Nancy Ammerman took a poignant look at practices of passing on faith in Mainline Protestant congregations. She found that most congregations at best put in less than an hour per week and details congregational behavior and practice in passing on the faith.
Let me state for the record that I am in favor of children participating in worship. However, "seeing" children/youth in worship is a short-sighted longing at best. Children and youth don't need to be seen in church as if their presence is an ego boost to the adults of the congregation. Children and youth are not to be paraded in front of a congregation because they are cute. Any interaction with children and youth in the life of the congregation involves an opportunity to teach them about faith in Christ and provide them an understanding of what it means to be part of a Christian community. It is not merely the task of the pastor, children's minister, or youth director to share faith with children and youth. Every group in the life of the church has something to pass on about what it means to be part of a Christian community. An altar guild, men's ministry, women's circle, Bible study group, food ministry, property committee, etc.--each have opportunities to pass on what it means to be part of a Christian community. On occasion I find a congregation that has no link to children and youth whatsoever. Even then, it is time for a congregation to look at the assets in a congregation for connecting with children and youth in some way without a preconceived expectation of how children will be "seen." Children and youth do not exist for our own glorification, but God's. A congregation in renewal will see in its community what can be given to children and youth rather than what they can get for having children and youth in the congregation.