Colter attended
Cherry Creek High School in
Denver, Colorado, where he was the team captain and a four-year letterwinner. He was also a three-time All-Centennial League selection. As a sophomore, he threw for 2,073 yards, ran for 463 and had 25 touchdowns. Playing a full season as a junior, he led the Bruins (11–3 in 2008) to the 5A state championship game as he threw for 1,786 yards, ran for 937 and accounted for 31
touchdowns. As a senior, he missed eight-plus games with a shoulder injury that limited his throwing, but still managed to finish with 907 passing yards and 978 rushing yards with 16 total touchdowns. In the quarterfinal game vs. defending state champ
Grandview High School, he ran 36 yards for the game-winning double OT score on a third-and-goal play. Colter also lettered three years in
basketball (playing
point guard) and four years in
track & field (competing in
long jump and
triple jump). As a high school senior at
Cherry Creek High School, Colter was rated as a three-star quarterback prospect by
Rivals.com. He was an All-Region quarterback according to SuperPrep All-Midlands, PrepStar All-Midlands Region and Rivals.com. He was ranked 52nd nationally among all athletes by Rivals.com, 49th nationally among all quarterbacks by SuperPrep and 56th regionally (nine states) among all players by SuperPrep. He also ranked seventh among all players in the state of
Colorado by Rivals.com and SuperPrep. Colter committed to
Northwestern University on January 14, 2010. Colter also received football scholarships from
Air Force,
Akron,
Arizona State,
Colorado,
Colorado State and
Stanford. In 2009, Kain Colter led a comeback against the then #1
Columbine High School Rebels, which ended in a game-winning field goal. He then moved to the 5A Colorado High School Championship Game against
Mullen High School. ==College career==