About the B'Nai Bagels — E.L. Konigsburg

Mark Setzer thought studying for his Bar Mitzvah and having his best friend move away created enough aggravation in his life. But then his mother becomes the new manager of his Little League team and drags his older brother, Spencer, along as coach. Miraculously, the team thrives, but in the process Mark learns some unpleasant truths about someone he thought he knew.