I was taught how to play infield by the absolute best infield instructor in baseball, Perry Hill. He is currently the infield coach for the Miami Marlins. He taught me everything when I was a second basemen with the Texas Rangers. He has also coached a number of Gold Glove winners.
Without sounding "salesy", please visit coachposting.com and purchase his instructional video. I swear it is the best $14.99 that you will ever spend on your son.
I love infield play. Send me a video at firstname.lastname@example.org and I would be happy to provide feedback. I don't know picthing, but I do know how to play the infield.
Remember, there is not a bad hop on the field. The infielder determines the hop.
Go get 'em.