7 Things Parents Do to Make Their Kids Hate Sports by All Pro Dad - Nice list of what not to do. Good comments too. Number 5 is probably the most common one I see.
Troubleshooting Baseball Hitting: Timing is Not Always the Problem by Jay Kolster, Cressey Performance - Good article on the mechanics that can help a hitter make timing a little less of a problem. Not enough young players focus on (or even know about) the correct positioning of the elbows and knees.
Trust Your Skills (Don't Think Too Much) by Jeffrey Rhoads, Inside Youth Sports - This one is important for young athletes. All the instruction and practice in the world won't matter if you can't relax and let it flow.