Jarrett attended Rockdale County High School in Conyers, Georgia, where he was a two-time All-state selection. A four-year starter on both sides of the ball, he had 198 tackles, 63 tackles for loss, and 27.5 sacks over his last two years. He was a three-time All-regional selection on defense and second-team All-region on offense as a senior, as well as a three-time selection as the team's top defensive player after compiling 101 tackles (31.5 for loss) and nine sacks.[1] He also played in the North-South All-Star game in Georgia and Florida Maxx Scout All-Star Bowl; in the two games combined, he had 17 tackles, seven tackles for loss, 3.5 sacks, and three caused fumbles.

In addition, Jarrett was also a member of the school's wrestling team; he was fourth in the state as a junior and won the state heavyweight title as a senior. Also a top performer in track & field, Jarrett won the state title in the shot put as a senior with a throw of 15.46 meters (50-6).[2]

Jarrett was rated by Rivals.com as a three-star recruit.[3] He was rated the No. 41 defensive tackle in the nation by Scout.com. He committed to Clemson University to play college football.[4]