This is all great advice except that sometimes a kid needs experience to get better and exude confidence. In our case, the HS coach was dealing with heavy donaters to the Booster's Club with a pitcher son. That coupled with the fact our son was an unknown to him, caused him to not put him in until the end of the season. It was one of those far reaches into the bullpen when the coach had exhausted all his pitchers. That kind of pressure without the experience didn't make for a good presence on the mound and made the HS coach reluctant to put him in the next season. I've seen this with batters too, the coach doesn't put a kid in until the 6th or 7th game and then by then the kid feels so much pressure to do well that they fold. While son still played on the HS team(mostly sat on the bench), we found him a coach on a travel team that did believe in him. Amazing what can happen when someone gives you a chance. He became their starting pitcher and brought the team to their first ever tournament championship. When the HS coach finally put him on the mound, son blew him away. Now he is their go-to closer and is being looked at by several colleges.
Politics were definitely in play on the team as it is in many places. But we just stayed away from the gossip/negative parents, and got him the experience he needed to get better. If your son isn't able to grow on the high school team and becomes a victim of the politics, DO NOT WAIT! Get him onto a reputable travel team and when he's a junior, a showcase team.