He doesnt need to get a hair cut. He doesnt need to play hs baseball. He needs to stand by his convictions and keep his hair if that is what is important to him. And then he needs to understand he is the one that will have to live with the decision that he has made.
When he cares enough about something to sacrifice in order to do it he will. Baseball is not important enough for a hair cut. Its that simple. With that attitude dont look for him to play past hs. I surely wouldnt waste my money on travel baseball in the summer on a kid who wouldnt get a hair cut to play hs baseball. Just play local rec league save your money for college tuition.