Carlton played his freshman season at South Central High School in Winterville, North Carolina.
His family moved to the Washington, D.C. area after his sophomore season and he enrolled at DeMatha Catholic High School.
[1] In September 2016, he committed to playing college basketball for UConn over offers from Cincinnati, USC, Providence, Maryland and Kansas State.
During his senior season, he lost his starting center role to Adama Sanogo and posted 3.5 points and 3.7 rebounds per game.
[5] He focused on losing weight and received more playing time due to injuries to Marcus Sasser and Tramon Mark.