Help for Outfielders

I am hoping someone out there can help me. I have been a little league coach for several years now and most of what I pass on to kids is through experence and some trial and error. But most of all have found instructional videos to be very helpful. Some more then others of course.

My problem is this. I can find a ton of books and videos on how to teach kids to hit, pitch, and some on playing infield. But NOTHING on how to teach kids to play the outfield. Has anyone out there found one, or at least can share with me some good drills to do to help outfielders. Especially on how to shag fly balls. I have found when a fly ball is hit to a kid in the outfield their first instinct is to move forward only to have the ball sail over their head and even land right where they were standing. Any advice would be helpful. Too many times in LL the kids playing the outfield are the forgotten ones on the team. I hope to correct that next season. At least on my team.