Below are characteristics of the “typical” child during the developmental stage of middle adolescence (ages 15-18).  Children’s progression through all stages of adolescence is determined not only by biological growth and change, but also by temperament and personality, adult expectations, the child’s environment, social influences. and the child’s past experiences.

Physical Growth

• Most youth have entered or completed puberty.
• Less variation in levels of growth and sexual development.
• Many youth have achieved their full adult height and other adult physical development milestones.

Cognitive Stage

• Major broadening of thinking abilities for many youth: can think abstractly and hypothetically; can discern the underlying principles of various phenomena and apply them to new situations; and can think about the future, considering many possibilities and logical outcomes of possible events.
• Greater perspective-taking ability can result in increased empathy and concern for others, and new interest in societal issues for many.

Moral Development

• Less egocentric with age. Increased emphasis on abstract values and moral principles.
• Increased ability (for some) to take another’s perspective; can see the bigger societal picture and might value moral principles over laws: “principled” morality.
• Different rates of cognitive and emotional development. For example, often advocates for specific values and violates them at the same time.

Self-Concept

• Process of identity formation is intense. Experimentation with different roles: looks, sexuality, values, friendships, ethnicity, and especially occupations.
• Some girls might experience obsessive dieting or eating disorders, especially those who have higher body fat, are chronically depressed, or who have highly conflicted family relationships.
• Minority youths might explore several patterns of identity formation:
  • a strong ethnic identity
  • bi-cultural identity
  • assimilation into the majority culture
  • alienation from the majority culture

Psychological and Emotional Traits

• For some, increased ability to empathize with others; greater vulnerability to worrying, depression, and concern for others, especially among girls.
• Many show an increase in responsible behaviors.

Relationship to Parents and Other Adults

• Conflicts with parents often decreases with age.
  • Improved ability to see parents as individuals and take their perspectives into account.
  • Most maintain good relationship with parents.
• Greater interest in taking on “adult-type” responsibilities (own checking account, doing own laundry, buying own clothes, cooking meals, making repairs, etc.).
• Commonly makes most of own decisions, preparing for eventual family.
• Needs balance between time spent with adults and with peers.
• Continue to benefit from some parental limits and monitoring, while often objecting to them.
• Common conflicts over money, curfews, chores, appearance, and activities with peers.

Peer Relationships

• Peers help youth explore and develop own identity.
• Cross-gender friendships become more common.
• Antisocial peer groups can increase antisocial behaviors.
• Close friendships help youth with process of developing an individual identity separate from that of a child in a family.

Information from Middle Childhood and Adolescent Development, Oregon State University Extension Service.