1996; Eccles et al., 1993; Jessor, 1993, 1998; Larson, 1994, 2000; Lerner and Galambos, 1998; Lerner et al., 2000; Lipsitz, et al., 1997; Metropolitan Life, 1994; Pittman et al., 2000b; Roth, 1996; Quinn, 1999). In this chapter, we provide an overview of what is known about development during the years from 10 to 18 so that individuals interested in community programs for youth have an accurate understanding of whom adolescents are and what they need as they design, fund, operate, and evaluate programs.
What is adolescent development really like? There is no doubt that it is a time of great change on many levels. Probably most dramatic are the biological changes associated with puberty, which include shifts in the shape of the body, increases in gonadol hormones, emergence of cyclical patterns of gonadol and related hormonal systems in females, onset of fertility, and changes in brain architecture and the receptivity of neurons to a variety of chemicals (Brooks-Gunn and Reiter, 1990; Buchanan et al., 1992; Gubba et al., 2000; Herbert and Martinez, 2001). These biological transitions are linked to changes in sexual interest, as well as to changes in both cognitive and physical capacities and emotional well-being. There are also major social changes associated with both school transitions and shifts in the roles that adolescents are expected to assume as they mature. Finally, there are major psychological changes linked to increasing social and cognitive maturity. In fact, few developmental periods are characterized by so many changes at so many different levels.
Adolescence is also a time when individuals in most Western and postindustrialized cultures make many choices and experiment with a wide variety of behaviors and experiences that can influence the rest of their lives (Brown and Corbett, forthcoming; Mortimer and Larson, 2002). For example, adolescents select which peer groups to join and how to spend their after-school hours. Adolescents make future educational and occupational plans and then pursue them through secondary school course work and out-of-school vocational and volunteer activities. Finally, some youth experiment with risky behaviors, such as tobacco use, alcohol and other drug use, and unprotected nonmarital sexual intercourse. For some of these youth, the experimentation has few or no long-term consequences; for others, this experimentation seriously compromises their future (Carnegie Corporation of New York, 1989; National Research Council, 1999c; Cairns and Cairns, 1994; Cicchetti and Toth, 1996; Elder and Conger, 2000; Jessor et al., 1991; Moffitt, 1993; Steinberg and Morris, 2001). Given the influence that these choices and behaviors can have over future life options, it is critical to understand