According to The Nemours Foundation...

"How much should my child weigh?" is a common question parents have.

The answer: "People have different body types, so there's no single number that's the right weight for everyone."

I urge you to check with your child's doctor about the healthiest weight for your 13 year old.

To calculate your teen's ideal body weight take 100 pounds for 60 inches of height plus 5 pounds (girls) and 6 pounds (boys) for each additional inch.

Dr. Hillary

That is a very important question. I don't think there is a height and weight that your child must be but i do think that the average 13 year old boy is around 130 - 135 pounds. As i said before it really depends on the height of your child. When I was 13 i weighed around 162 pounds but i was also very muscular and muscle weighs more than fat. You really shouldn't want to know your child's weight, but you should want to know your child's strength and cardiovascular strength.

95

there's no exactlly the weigh of a 13 years old child but you  if your child is no longer be able to control his /her own body , he/she might be obersity that's where she need to see a doctor  so that they can advice her/he how to restore and maintain  the normal weight.