average growth of male teens in a year
Teens going through puberty will have many changes in their developing bodies as growth surges and muscles change shape. Most girls start their sexual development between the ages of 8 and 13 (the average age is 12), and have a growth spurt between the ages of 10 and 14. Most boys start developing sexually between the ages of 10 and 13, and continue to grow until they're around 16.