- begin around 10 1/2 to 13

-they get red, dark, and wrinkled

- sperm is made between 14 1/2 to 18 years old

- starts as soft hair

-becomes curly about 10  - 15 yeard old

- hair gets more curly after first ejaculation

- can grow 3 -5 inches in a year

- by 16 boys will have reached 98% of their height. 

They grow fast!

- Two Step Process

a.  gets a little deeper before 1st ejaculation

b.  becomes the "man voice after first ejaculation

- begins to grow first in corners of the mouth

- then lips

- then cheeks

- finally a beard