Kevin attended Lake Oswego High School, where he played for the Lakers. He quickly became a standout player, averaging an impressive 25.3 points, 15.4 rebounds, and 3.7 assists per game in his sophomore season. His outstanding performances led the Lakers to the 2005 state championship game, where they narrowly lost to Jesuit High School.

Despite this setback, Kevin continued to improve his game and attracted the attention of basketball scouts and coaches across the country. In his junior season, he averaged a remarkable 28 points, 16.1 rebounds, and 3.5 assists per game, leading the Lakers back to the state championship game and this time winning it with 24 points and 9 rebounds by Kevin.

In his senior year, Kevin took his game to new heights, averaging an incredible 33.9 points, 17.0 rebounds, and 4 assists per game. He led the Lakers to their third straight state championship game, but they lost in a rematch of the prior year's final to South Medford High School and Kevin's rival Kyle Singler, despite Kevin's 37 points.

At the conclusion of the season, Kevin was named the Gatorade National Male Athlete of the Year, the first basketball player to receive the prestigious award since LeBron James. He was also a first-team Parade All-American and finished his high school career as the all-time leading scorer in Oregon boys' basketball history, with 2,628 points.

Kevin's outstanding performances in high school earned him a scholarship to UCLA, where he played college basketball for one season before being drafted by the Memphis Grizzlies in the first round of the 2008 NBA draft. Since then, he has played for several NBA teams, including the Minnesota Timberwolves and the Cleveland Cavaliers, and has won an NBA championship with the latter.