have your kid talk to the coach about playing time, don't do it yourself. It's obviously different for rec leagues, but on high school and comp teams, there's probably a good reason your kid isn't playing as much as others. If your child approaches the coach and says "what can I do to get more playing time?" they will probably leave that meeting with a clear understanding of what they need to improve on, and the coach knows that they're willing to work on. But if a parent comes in and asks why Johnny/Sally isn't playing more, you'll probably just annoy the coach and you're robbing your kid a chance of an opportunity to grow.