Have you ever taken out a few books or videos from the library on pitching or hitting, only to find that the advice from each source is wildly contradictory?
Have you ever tried to help your youngster unlock the secrets of baseball, only to find that many coaches simply pass on the same mumbo-jumbo that others passed on to them?
I found that it's awfully hard to tell the good advice from the bad advice. Partly because most coaches (1) don't explain why their advice is sound, (2) don't have much insight on the relevant physics or physiology, (3) haven't tested their own advice much, and (4) don't use tools like slow-motion cameras to see what's really happening.
A few months ago, I found a guy named Chris O'Leary who has covered all four of those bases and more. On his website, he has gone a long way toward exploding many misconceptions that proliferate on Little League fields. For example, the balance point myth in pitching and the myth of the level swing in hitting.
Although he has virtually no baseball background other than playing in elementary school, his website is a treasure-trove of clear thinking and useful insights. The site is well illustrated with videos and stop-action photos.
If you want to start with pitching, go here. For hitting, go here.