Just to be sure you're addressing the problem, is she actually crow-hopping or jumping? A crow-hop is when the pivot or push-off foot is brought forward to a point where it is replanted and provides for an additional drive forward. A jump is when both feet leave the ground in an effort to maximize effort and minimize distance to the plate -- it's what was being called IP during the College championships -- the guilty were leaving the ground with the pushoff foot.
I've found most of my pitchers who jump also tend to be forward leaners. Getting them upright or a slight back lean at the K point helps to keep the foot in contact with the ground.
jim
Thanks for the response redhawkridge. She is definitely replanting and pushing from the spot. She does keep her weight back on the pitches that require it so leaning is not a problem. Coach Stan's suggestion of using a rag under her push foot is a good idea, but I am not sure that simply moving it forward will correct the crow hop. She currently drags with the side of her right toe ( she is right handed ) in contact with the ground. I know that Michele Smith has said that if you roll your foot over onto the tip of the toe it will prevent a crow hop. I think that the 2 x 4 exercise that Sanchosj suggested is designed to train the foot to do that. I will be working with her later this week and will begin to try these suggestions. Thanks