Here's a video on the importance of letting the coach do his job during matches. We don't really have a problem with this on our team, but our goal is to keep it that way. I've ran into this problem with several other teams, including between other coaches at the high school level. It confuses the wrestler when they don't know who to listen to or can't hear the strategy because several people are screaming at once. Louder does not equal better. Let the coach coach.
All of us are crunched for time in the evenings, but there is no secret to kids getting good in the long run. It is simply getting them to practice over and over and over and keeping them motivated. Us coaches are the same as many of you parents. We come straight from work, pick up our kids, and then practice until 8:30 or sometimes 9, then we go home, cook dinner, kids finally shower, maybe we shower, then we prep for the next day's practice and prep for the next actual work