Whittington had a standout rookie year in the NBA’s D-League last season, being named on the All-rookie team. He finished the year guiding the Sioux Falls Skyforce to a D-League Championship. He previously played for the Georgetown Hoyas in College and was All-Met Player of the Year and Howard County Player of the Year playing for Oakland Mills High School in his home-state of Maryland. He led his team to an undefeated season, finishing 25–0.
Averaged 14 points, 8 rebounds, 3 assists, 2 steals and two 3s per game in the 1015-16 season with the SkyForce.
He averaged 12 points and 7 rebounds in the 2012-13 season with Georgetown.
As a senior, playing for Oakland Mills High School he averaged 23.5 points, 11.6 rebounds, 4.4 blocks, 3.0 steals and 2.7 assists per game.