Baseball Heroes is the first book in the new middle grade nonfiction series Good Sports, about the inspiring life stories of major league athletes who have overcome obstacles in the course of their life and careers.   Each book tells the stories of athletes who have encountered and overcome significant obstacles, and whose story exempifies character and nerve in the face of adversity.  Baseball Heroes highlights players who were among the first to break through barriers of race, ethnicity and even sex in order to play professional baseball. Subjects include Jackie Robinson, Hank Greenburg, Fernando Valenzuela, and Ila Borders.