The development of children ages 12 through 18 years old should include expected physical and mental milestones.
Information
During adolescence, children develop the ability to:
- Understand abstract ideas. These include grasping higher math concepts, and developing moral philosophies, including rights and privileges.
- Establish and maintain satisfying relationships. Adolescents will learn to share intimacy without feeling worried or inhibited.
- Move toward a more mature sense of themselves and their purpose.
- Question old values without losing their identity.
PHYSICAL DEVELOPMENT
During adolescence, young people go through many changes as they move into physical maturity. Early, prepubescent changes occur when the secondary sexual characteristics appear.
Girls:
- Girls may begin to develop breast buds as early as 8 years old. Breasts develop fully between ages 12 and 18.
- Pubic hair, armpit and leg hair usually begin to grow at about age 9 or 10, and reach adult patterns at about 13 to 14 years.
- Menarche (the beginning of menstrual periods) typically occurs about 2 years after early breast and pubic hair appear. It may occur as early as age 9, or as late as age 16. The average age of menstruation in the United States is about 12 years.
- Girls growth spurt peaks around age 11.5 and slows around age 16.
Boys:
- Boys may begin to notice that their testicles and scrotum grow as early as age 9. Soon, the penis begins to lengthen. By age 17 or 18, their genitals are usually at their adult size and shape.
- Pubic hair growth, as well as armpit, leg, chest, and facial hair, begins in boys at about age 12, and reaches adult patterns at about 17 to 18 years.
- Boys do not start puberty with a sudden incident, like the beginning of menstrual periods in girls. Having regular nocturnal emissions (wet dreams) marks the beginning of puberty in boys. Wet dreams typically start between ages 13 and 17. The average age is about 14 and a half years.
- Boys’ voices change at the same time as the penis grows. Nocturnal emissions occur with the peak of the height spurt.
- Boys’ growth spurt peaks around age 13 and a half and slows around age 18.
BEHAVIOR
The sudden and rapid physical changes that adolescents go through make adolescents very self-conscious. They are sensitive, and worried about their own body changes. They may make painful comparisons about themselves with their peers.
Physical changes may not occur in a smooth, regular schedule. Therefore, adolescents may go through awkward stages, both in their appearance and physical coordination. Girls may be anxious if they are not ready for the beginning of their menstrual periods. Boys may worry if they do not know about nocturnal emissions.
During adolescence, it is normal for young people to begin to separate from their parents and make their own identity. In some cases, this may occur without a problem from their parents and other family members. However, this may lead to conflict in some families as the parents try to keep control.
