The second phase of adolescence, middle adolescence, is roughly from the age of 15 to 17 years. In this stage, although most of the physical changes of puberty have taken place and your teen is pretty close to his or her adult height, there's plenty of inner construction work still occurring. While teens at this age are very concerned with their appearance and spend a lot of time grooming or experimenting with makeup, they may also refuse to wash, tidy up their room, or dress neatly. They become concerned over their attractiveness toward the opposite sex, and are less likely to develop a crush on a member of the same sex at this age.
They still chafe at their parents' control and struggle to assert their independence, with a heightened level of conflict. Although middle adolescents need their parents' love and acceptance, they think they'll appear more mature if they hide this need. They continue to feel invincible, as they did in early adolescence, and they often exhibit risky behavior, whether via alcohol, drugs, sex, cigarettes, or a combination. The middle adolescent's peers are still all-important, and loss of peer approval is devastating. They are better able to express themselves through speech, so incidences of acting out decrease, and they are actually able to say no to peer pressure… if they choose to. If their special academic, artistic, musical, or athletic talents are encouraged, their self-esteem will increase, the better they'll feel about themselves, and the more they'll be able to trust their inner voice.
Although their view of the present now widens into the future and they can consider a future career, their cause-and-effect thinking is still fuzzy and they have a hard time connecting drunk driving with car accidents or sex with pregnancy and STDs. In addition, no matter how smart your teens are, they lack experience in dealing with all types of people and may fall for someone who's a smooth talker.