As a senior in high school, Edmondson played prep basketball at University Heights Academy in Hopkinsville, Kentucky under head coach Randy McCoy. Edmondson averaged 18.4 points, 6.7 rebounds, 4.3 assists, and 2.7 steals per game, powering his team to a Kentucky High School Athletic Association (KHSAA) district and regional title. Among the guard's teammates was Scotty Hopson, who would go on to play college basketball at Tennessee. Edmondson also earned most valuable player honors at the Kentucky All "A" Tournament. UHA finished the season with a 30–5 record.[4]