Here's a friendly suggestion to any high school coaches reading this thread: dedicate five minutes of your your preseason orientation speech to this topic so that your players and families know where you stand....
Wow, great idea! I'm sure the parents will remember what you said two months later when it suddenly becomes an issue for THEIR KID. And, surely all of the parents that REALLY NEED TO BE THERE will be.
Sorry Tribe, I couldn't resist. I can't tell you how much effort we've put into covering every possible issue in our meetings over the years only to have the parents who need it most not show or somehow be in another discussion in the back corner when they need to hear what is being said.
We have tried everything regarding mandatory attendance and attention but you'll always have a few of THOSE parents and, in that case, we also try not to penalize the poor kid.