An infant triples her birth weight in just one year and grows in length by nearly 50 percent. She becomes mobile, rolling over from 3 to 6 months, crawling at 9 months and cruising and walking shortly after her first birthday. From here, physical development slows as she grows about 2 1/2 inches taller and gains 4 to 7 pounds each year until adolescence, according to KidsHealth.
By age 4, a child can hop while balancing on one foot, the National Institutes of Health explains. A 7-year-old's developing fine motor skills make her increasingly skilled at coloring, while her gross motor skills enable her to play ball games, dance and skip. In late childhood, strength, stamina and hand-eye coordination progress rapidly.
The teen years are characterized by puberty, where secondary sex characteristics develop and rapid musculoskeletal growth takes place, explains KidsHealth.