The 1998 Track & Field News National High School Athlete of the Year, Yeldell was also a 2-time North Carolina Gatorade Track & Field Athlete of the Year (1997, 1998). 

The All-American won the World Junior bronze medal in the triple jump, the U.S. Junior triple jump title, and the national indoor and outdoor triple jump titles (1998). He held the national high school triple jump record for six years (and is still No. 2 all-time at 53-feet, 11.75 inches), and he also holds the all-time best triple jump marks in North Carolina in indoor track (52-2.75) and outdoor track (53-11.75). 

Greg won MVP of the 1998 all-class indoor state meet by winning 3 events and helping North Rowan to the team title. In all, he won 4 state indoor titles – 1 in the long jump (1998), 2 in the triple jump (1996, ’98) and 1 in the high jump (1998), and still holds the all-class triple jump indoor state championship meet record. In outdoor track, he is a 3-time N.C. 2A Championships meet MVP (1996, ’97, ’98) and a 7-time N.C. 2A state champion – 4 in the triple jump (1995, ’96, ’97, ’98) and 3 in the long jump (1996, ’97, ’98), helping North Rowan to 4 state outdoor team titles (1995, ’96, ’97, ’98).