While attending the University of North Carolina, Justin Jackson remembers Harry Giles visiting when he was in high school. From those visits, Jackson recalls Giles being a "monster" on the basketball floor. While at Oak Hill and Wesleyan Christian Academies, Giles earned a First Team All-USA selection by USA Today and as a junior in 2015, averaged 23.9 points and 12.5 rebounds. He later was rated the No. 1 overall recruit in his class by ESPN, as well as No. 2 overall by Rivals, Scout and 247 Sports.
He would go on to attend Duke University, but a string of injuries (ACL tears in both knees and an MCL tear in his left knee) put a damper on that hype.