Puberty is a time when the boy or girl becomes sexually mature. Puberty is an exciting phase for kids. Although the physical aspect of puberty triggers curiosity, the psychological aspects are also equally exciting. It is the stage when the appropriate hormones start acting slowly and steadily. As a result, boys gradually become men, and girls are on their way to becoming women.
It starts at between the ages 10 and 14 for girls and ages 11 and 16 for boys. Since the range for starting puberty is quite broad, it is not unusual to have a kid start and progress in puberty, but another kid of the same age not having any signs of puberty. However, these age ranges are not strict, and normal puberty in a small number of kids can start below this age.
There is a small gland in the head called the pituitary responsible for producing gonadotropins that start puberty. This gland is regulated by an area of the brain called the hypothalamus responsible for deciding the timing of puberty. The gonadotropins act on the testes (in boys) and ovaries (in girls) and produce hormones -testosterone (in boys) and estrogen (in girls). These hormones lead to most of the changes that we see externally in boys and girls in puberty.

Dr. Mathew John