For a printer-friendly version, click here . Introduction Adolescence is a time of transition between childhood and adulthood. It is important to view adolescence as a process of incremental changes. It is generally accepted that the beginning of adolescence is marked by the development of secondary sex characteristics, i.e., body hair for boys and girls as well as ejaculation for boys and menstruation for girls. Boys and girls develop at different ages and different rates.
Girls generally precede boys by approximately two years.
Girls can begin to show signs of development as early as age nine, where boys usually begin to show signs of development at age eleven. It is common to see physical changes in both sexes by fifth grade. When recalling their first conscious sexual thoughts, most students report these occurred at about age nine years. Sexual development is a major part of adolescence. Sexuality flows from the onset of physical changes.