Boys 11 years old body grows a lot of hair, consider it a normal phenomenon. Because 11-year-old boys have entered puberty, there will be the development of secondary sexual characteristics. And boys generally 11 years old around the age of puberty, there will be the development of secondary sexual characteristics, manifested in the male penis, testicles enlargement, body hair, armpit hair increase, prominent knot in the throat, low voice, muscular development, lips appear whiskers and so on. So a lot of hair growing on the body is considered a normal phenomenon. Moreover, the early and late development of the secondary sexual characteristics of boys is related to many factors such as heredity and nutrition. If parents are worried about their children, they can take their children to the endocrinology department of the hospital for examination to exclude the possibility of lesions.