My DD and I practiced during the winter at a baseball academy that had a radar gun set up in the tube. The radar gun was hooked up to a digital readout located directly behind me (the catcher). So, she would throw a pitch and then see immediately how fast she threw. When we worked on speed, it became a game with her. It was "her vs. the machine". I would have to drag her out of the place on some nights. A couple of times, the owner was literally turning out the lights on us when she finally quit.
