Simpson grew up in Panorama City, Los Angeles and attended Chaminade College Preparatory School.

[1] He was rated a four-star recruit and initially committed to playing college basketball for Arizona.

[2] After Arizona head coach Sean Miller was fired, Simpson requested and was granted a release from his National Letter of Intent and reopened his recruitment.

[6] As a junior, Simpson was named to the first-team All-Pac-12, averaging a team-high 19.7 points per game and shooting 43% from three-point range this season.

7 Florida, Simpson hit a game-winning jumper with less than two seconds left to secure a 102–100 victory.