When Beverly Hills High School welcomed a skinny boy from the other side of the tracks, no one knew just how life-changing the decision would be, not just for Carter Paysinger but for all of Beverly Hills.

Carter grew up hearing his parents say, "Don't just strive to be good. Always strive to be great." He dreamed of finding greatness in playing professional baseball or becoming a black Donald Trump, but fate had different plans and, ultimately, he found his calling as a teacher and coach at the school that once embraced him, becoming a rock for the innumerable kids who came seeking an...