Adolescence is the period between childhood and adulthood. It usually begins somewhere between the ages of 11 and 15. Girls often show the physical changes of adolescence earlier than boys. Growth during adolescence takes place physically, mentally, and socially. Many of the changes you will experience during adolescence are brought about by hormones. These hormones and the changes they cause during your teen years are preparing you for adulthood. Let’s look at some of the changes in more detail.