The three-star prospect chose the Vols over offers from Oklahoma, Purdue, VCU, Houston, UTEP and Wake Forest.
"When I called coach (Cuonzo) Martin tonight to tell him I committed, he told me that I resemble him a lot from when he was a player," Cornish told the newspaper. "That's what he likes about me -- that toughness that I bring to the table. That's what he bases his program on -- toughness -- and I want to be a part of it."
Cornish plays for the Team Louisiana travel squad in the Nike EYBL. He is the first recruit from the 2014 class for Tennessee.