McKenney was born on September 6, 2006, the son of Jasmine (Stanley) and John McKenney. and grew up watching
Michigan Wolverines basketball with his father. McKenney's maternal grandfather is
Woodrow Stanley, a former
Mayor of Flint, and his Aunt, Linnell Jones McKenney, is regarded as Flint's first female professional basketball player. Flint has a strong basketball history, including local high school greats such as
Glen Rice,
Morris Peterson,
Mateen Cleaves and
Charlie Bell having played high school ball there. However, by the 21st century, local legends such as
Kyle Kuzma,
JaVale McGee and
Miles Bridges played high school at distant
prep schools. McKenney also left the Flint area to attend
St. Mary's Preparatory, a residential private school located 45 minutes from Flint. According to his own
Twitter account, McKenney received his 6th NCAA Division 1 scholarship offer (from
Illinois) on November 17, 2021, as a freshman. By the end of 2021, he also had offers from Michigan and
Alabama. In June 2022, following his freshman season, his offers list included Alabama,
Arizona State,
DePaul,
Eastern Michigan, Illinois,
Indiana, Michigan,
Ohio State,
TCU,
Temple and
Texas. As a sophomore, he led St. Mary's to a surprise 2023
MHSAA Division 1 semifinal appearance, despite an 11–10 regular season record and a last place 2–8 division performance. As a junior, McKenney led St. Mary's to a 27–1 record and the 2024 MHSAA Division 1 state championship, scoring 32 points and 10 rebounds in a victory over North Farmington on March 16. In the game, McKenney made 8-of-11
field goals and all 14
free throws. St. Mary's was the number-one ranked school in the state for the entire season. Following his junior year, McKenney represented the
United States national team at the
2024 FIBA Under-18 AmeriCup in Argentina, winning a
gold medal. He started all six games for the undefeated team USA, averaging 10.8 points, 5.3 rebounds, 2.2 assists and 1.3 steals in 18.8 minutes. McKenney finished second on the team in scoring. McKenney and Acuff played together on the same
AAU team, The Family, in the
Nike Elite Youth Basketball League (EYBL). When they were both sophomores in Michigan with their high school teams, McKenney was the 2023 Michigan
Associated Press (AP) Division 1 Player of the Year at St. Mary's. However, when they played together for Team USA, Acuff was the MVP of the 2024 FIBA Under-18 AmeriCup. McKenney won the Michigan AP Player of the Year for a second consecutive season as a junior in 2024. He also was named the Michigan
MaxPreps Player of the Year, Michigan
Gatorade Player of the Year and the Detroit High School Sports Athlete of the Year. As a junior, he averaged 22.9 points, 10.1 rebounds and 2.5 assists per game. McKenney entered his senior season as one of the top 25 players in the nation according to
Sports Illustrated. In December 2024, at the Motor City Roundball Classic, McKenney became the all-time leading scorer in St. Mary's basketball history, passing former Michigan State guard
Kalin Lucas' mark of 1,688 career points. As seniors, McKenney and Acuff met in an interstate matchup, with IMG Academy and St. Mary's playing each other in a closely contested regular season game. St. Mary's led for three quarters before IMG went on to win 67–62. McKenney finished with 37 points on 12-of-17 shooting, with eight made threes, and Acuff was 11-of-19, with 32 points and four made three-point shots. In January 2025, McKenney was named a
McDonald's All-American. He was the first Michigan signee to be selected since
Moussa Diabaté,
Caleb Houstan and
Kobe Bufkin in 2021, and would be the first to play in the game since
Daniel Horton in 2002 (due to the
COVID-19 cancellation in 2021). In February 2025, McKenney led St. Mary's to back-to-back Catholic League titles and a third in four years, defeating the No. 1 team in the state, U of D Jesuit. He had a 22 point, 10 rebound performance. In the state playoffs, St. Mary's advanced to the 2025 MHSAA Division 1 semifinals before losing to
East Lansing. In March 2025, McKenney was named
Mr. Basketball of Michigan. He also repeated as Michigan's Gatorade Player of the Year and MaxPreps Player of the Year in 2025. As well as being awarded Michigan's AP Player of the Year for a third consecutive season. As a senior, he averaged 23.8 points, 10.2 rebounds and 3.0 assists per game, finishing the season shooting 55% from the floor and 42% from three-point range. He finished his high school career at St. Mary's with 1,970 total points scored and a 79–22 overall record (including three straight MHSAA state semifinal appearances). While representing the USA junior national team against the world in the Nike Hoop Summit, McKenney scored 22 points, including nine points in overtime to lead the United States to a victory. ==College career==