Boys enter puberty at the age of 11-13 years old, at the age when development is considered normal, in terms of height the average height increases by 6.6cm per year from the age of 11-13 years old, weight increases by an average of 5.5kg per year, the sexual organs will show rapid testicular development. 14-15 years old is close to adult size, the vulva starts to change from short and fine pubic hair at the age of 12-13 years old, gradually starts to become thick pubic hair, and will appear At the age of 14-15, the male voice becomes lower, the laryngeal nodes increase, and the bones grow stronger.