and low self-
             esteem, and self-esteem decreases in adolescence, it is important for us to find out the
             causes of negative self-concept and low self-esteem of adolescents. And then help them
             to make adjustments. There are several main causes, which contribute to modify the self-
             concept and self-esteem, such as physical appearance, social contexts, scholastic and job
             competence, athletic competence, close friendship, and social class.
             As we transmit from childhood to adolescence, we perceive ourselves that the physical appearance changes. For example, male increases penis and testicle size, appearance of kinky pubic hair, and so on. Female's breasts enlarge, pubic hair appears, and hips become wider than her shoulders, and so on. Since the physical appearance changes due to puberty, both male and female feel negative about their body image, then the self-esteem declines. Moreover, females' self-esteem would decline during early adolescence because they have more negative body images than the males. As a result, the adolescents seek endless to modify their physical appearance in order to conform to the picture they wish to show in front of the others. However, there is fewer people notice than they presume in reality. For example, many girls between 12 to 17 years old would like to pursue the body image of Miss America. Since their body weight increases during the puberty, their arms and the legs become thick they attend the weight-loss program of beauty shop or hospital. Moreover, the boys clean the beard in order to look good in front of the people. One-way to increase the adolescents' self-esteem is accepting their puberty changes, not only others, but also themselves. Since then, the adolescents observe puberty changes as normal developments of body and the body images become more positive.
             Social contexts such as the family, peers, and schools have great impact the self-esteem of an adolescent. Acc...