average height and weight for children
Birth. The average newborn is 19.5 inches long and weighs 7.25 pounds. Boys have a head circumference of about 13.5 inches and girls measure in at 13.3 inches, according to the National Center for Health Statistics.1  Baby Growth Charts: Calculate Height and Weight.2  Charting Baby's Development.ges 5+. Kids will grow about 2 inches and gain 4 pounds each year until puberty (usually between 8 and 13 for girls and 10 and 14 for boys). Girls often reach their full height about two years after their first period. Boys usually hit their adult height around age 17.