According to the rule book..the minimum length is 35.5 inches and the maximum is 43.25 inches....but, the general rule of thumb is to put the butt of the stick in the girl's armpit and have her hold her arm out to the side, where her hand grasps should be just below the head after the handle has been cut. i typically have the parents leave the stick a little longer and see if that's workable - then they aren't buying another shaft after a growth spurt.