American culture invented “teenagers," and youth ministry was created as missionary ministry to teens. Believe it or not, the term “teenager” was never used until 1941. Of course, the fact of adolescence is ancient. After all, the book of Proverbs is written to address the young adolescent man. But the social function of the adolescent years changed during the latter half of the nineteenth and early twentieth century. What emerged during the decades following the industrial revolution was a distinct adolescent culture that differed radically from the culture of parents and other adults. The teenage years were no longer viewed as an intermediary life-stage with adulthood as the goal but a distinctive “youth culture” or “orientation” that resisted movement toward adulthood. The late 19th and 20th-century church responded to this phenomenon with a legion of age-focused ministries. These began as para-church ministries (the YMCA, Young Life, Youth for Christ). These were evangelistic and youth missionary movements that gave us leaders like D.L. Moody and Adoniram Judson. The para-church youth movement was innovative and successful. Because of its success, church youth groups began to imitate the para-church ministry models, and they have experienced years of success.
In more recent years, youth groups have developed their own distinct expressions of Christian community disconnected from the faith of their mothers and fathers. Youth ministries have often pursued their own ends, connected to the larger church’s vision like one of Mickey Mouse's ears (that is, barely connected at all). In our day, 70% of teens are leaving the church by their sophomore year in college. Many blame the church's compartmentalized and segmented ministry to youth. In response to this situation, the family ministry movement has begun.
 Timothy Paul Jones, “Chapter 3—Historical Contexts for Family Ministry,” in Perspectives on Family Ministry, ed. Timothy Paul Jones, (B & H Academic, 2009), pages 26-36; Tim Chester and Steve Timmis, “Chapter 12—Children and Young People,” in Total Church: A Radical Reshaping around Gospel and Community, (Crossway, 2009), pages 181-190. For my own part, I don't see the connection between the youth ministry model and this statistic. However, as I'll write in the next segment, I'm happy with the family ministry movement's adjustments.