I usually keep statistics (actually have my assistance keep stats) while I watch the players. You can teach a kid to hit, field and throw...you can't teach them to have drive or heart. I watch for those little things in kids that just can't be taught. I would rather have a kid who was a good runner, good hitter, good arm and had the will, determination and desire to do what ever I instructed them to do with the desire to learn. Than a kid who was really fast and had a poor attitude or was lazy and didn't listen. Try to remember quotes and sayings "one bad apple will ruin the bunch" they've been around for so long for a reason. It will also allow you to better assess where kids can and should play...Hope this helps.