Normal Development: 15 to 17 Years Old


Adolescence is divided into 3 stages: early (12 to 14 years), middle (15 to 17 years), and late (18 to 20 years). While certain attitudes, behaviors, and physical milestones tend to occur at certain ages, a wide spectrum of growth and behavior for each age is normal. Consequently, these guidelines are offered as a way of showing a general progression through the developmental stages rather than as fixed requirements. It is perfectly natural for a teen to attain some milestones earlier and other milestones later than the general trend.

Physical Development

  • Most girls have completed the physical changes related to puberty by age 15.
  • Boys are still maturing and gaining strength, muscle mass, and height and are completing the development of sexual traits.

Emotional Development

  • May have anxiety over school and test scores.
  • Is self-involved (may have high expectations and low self-concept).
  • Seeks privacy and time alone.
  • Is concerned about physical and sexual attractiveness.
  • May complain that parents prevent him or her from doing things independently.
  • Starts to integrate both physical and emotional intimacy into relationships.

Social Development

  • Is increasingly aware of social behaviors of friends.
  • Seeks friends that share similar beliefs, values, and interests. Friends become more important.
  • Starts to have more intellectual interests.
  • May be influenced by peers to try risky behaviors (alcohol, tobacco, sex).

Mental Development

  • Becomes better able to set goals and think in terms of the future.
  • Has a better understanding of complex interrelationships of problems and issues.
  • Starts to develop moral ideals and to select role models.


If you have any concerns related to your teen's own pattern of development, check with your health care provider.

Pediatric Advisor 2006.4; Copyright © 2006 McKesson Corporation and/or one of its subsidiaries. All Rights Reserved. Developed by McKesson Provider Technologies. This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.