9. Jim Ryun
Sport: Track & Field
Achievements as a Teen: Jim Ryun was the first high schooler ever to run a sub-four minute mile, running 3:59.0 as a junior. In 1966, he broke the world record at age 19, with a time of 3:51.3, and that same year he set world records in the mile and half-mile runs. The year got even sweeter when he took home Sports Illustrated's "Sportsman of the Year" award, in addition to the James E. Sullivan Award as the nation's top amateur athlete.
Career Recap: Ryun finished with four world records and was the Track and Field News Athlete of the Year winner in 1966 and 1967, the first athlete to win the award in consecutive years. Add that to the 1966 SI "Sportsman of the Year" award, the 1966 James E. Sullivan award, and the 1966 ABC Wide World of Sports Athlete of the Year award. Run Ryun, run.