How much are you supposed to weigh at 9 years old?

My friend is 9 yearsold. her and her classmates usually weigh 90-96 pounds. being 100 or over is overweight. but if your 5 foot, its perfect. under 60 pounds for usually 4-5 feet is weigh to skinny. if your about 4-5 feet and weigh 69,70,71 pounds, try eating more. your body needs lots of protein and Vitamin's. when i was nine, i was 4 foot nine and weighed 91 pounds. lets say your 4 foot 5 or 3. you should weigh 76-83 pounds. if your 5 foot 1, you should weigh 100 pounds. 100 pounds is not fat, it is perfect.