Do you know what a "bone age" is? A kid can get an xray of his/her hand at a young age, and it will accurately project their adult height. Its a great recruiting tool.
And yeah I saw an endocrinologist as a child and got a bone age when I was 12. It said I would grow up to be 5'7". I'm 26 years old and 5'7"
My basic point is that I find it creepy to be evaluating 12yo little boys.
Had roughly the same thing done when I was in 8th grade (so... 14yo). I was just under 5' tall and under 100 pounds at the time.
I had a late growth spurt to put me around 6'1" by the time I graduated HS, but still only weighed 108. I'm downright portly at 150 lbs today.