During adolescence, young people go through many changes as they move from childhood into teenagers. Between the ages of 11~16 a young girls breasts will have started to develop and will have fully developed between 12~18 years old. A girls menstrual cycle may start as early as 12 and as late as 15. Pubic, armpit and underarm hair will grow equivalent to that of an adults at around 13~14 years old. Boys may begin to notice that their testicles and scrotum are growing and by the age of 16 or 17 their genitals are usually at their adult size. Pubic as well as armpit, leg, chest and facial hair begins to grow at about age 12 and is equivalent to that of an adult about 15 to 16 years. Physically, teenagers become much stronger and develop gross motor skills through a wide range of sports. Fine motor skills could consist of knitting, sewing, along with arts and crafts. By the time an adolescent has reached 19 years old, they could be sexually active and have children themselves. Some could be taller than their parents. A lot of teenagers who are going through these changes could be worried about personal image i.e. weight issues and how they look.
Intellectual: At 12~16, a young adolescent will be entering a crucial stage in their lives, most will be making a transition from junior school to secondary school, there they will develop the ability to use their initiative e.g. taking options at school and may have a clear preference to arts or science. Teenagers become less sociable towards their parents and peers. Communication becomes less and more aggressive. At this age it is important for a young adolescent to fit in and not appear different from his/her peers therefore image and personal appearance becomes more important.
Between 16~19 years of age young adolescents begin to think about their future. For some, 6th form or college may be an option; others may choose not to pursue further education and go to work. Adolescents develop the ability to speak rather than to ‘act out’ and relationships with parents and peers improve and become more honest and open. Peer group relationships may well be replaced by individual friendships and by this age a number of youths could be experiencing intimate relationships and a small amount may have children themselves
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