Since age 13 is a crucial stage for adolescence, the body goes through various changes that are inconsistent in nature. Weight is another aspect that can be affected by multiple factors like height, gender and body frame. Unlike the weight chart, a standardized chart for height would not suffice. However, according to the Centers for Disease Control and Prevention 13-year-old girls weigh between 34.4 kg and 54.3 kg and boys between 35.8 kg to 55.7 kg