Sometimes how you say something makes a difference in getting across a corrective measure. Practice wrapping your correction, given in a positive way, with two compliments.
* Open with something like, `Beth, you're really trying hard to catch the ball, and I'm proud of your effort.`
* Say and show, if possible, your correction:
`Here's a way to catch evenmore balls -- if the ball is above your chest, point the fingers of you glove upto the sky; if it's low, point the fingers down.`