Growing up, Reid was confused and disturbed by the radically different opportunities his best friend received. After a childhood spent together, Jamie and Reid found themselves on opposite sides of a high school hallway that separated kids based on a misunderstanding of their supposed "potential." The gap between the two friends widened as Reid's classes enabled him to pursue an elite college degree across the country studying educational opportunity and teaching. Then, Reid became a teacher at an under-resourced South Carolina high school where efforts to serve the incredible students were stymied by internal segregation and administrative ambivalence. He was disabused of the Hollywood myth that a good teacher could simply save the day, when each false start with his students forced him to reckon with how much he didn't know. After Reid assigned students a project to create a positive change, they pushed him to figure out how he, too, could make a bigger difference. While an individual's efforts are no match against entrenched systems, Reid learned firsthand that a community of people powered by data can effect change. This lesson motivated him to found Equal Opportunity Schools (EOS), a nationwide nonprofit dedicated to finding the students who were overlooked, discouraged, or otherwise missing from higher-level classes. As EOS became more successful, partnering with major philanthropies, universities, and even the White House, Reid grappled with his role as a leader. Only through the efforts of, first, his students in South Carolina, and later his team at EOS, would he come to understand, and begin to overcome, the limitations of his vision. Informed by extensive new data on educational opportunity in America, The Kid Across the Hall is a powerful story of learning and unlearning; of leading and learning to follow.