He led Hillsdale to consecutive undefeated seasons in 1955 and 1956 and was selected as a first-team back on the Little All-America teams in both years.

[1] He excelled in sports and appeared in every football game for Benton Harbor High School from 1949 to 1952.

[7] In 1955, Clark rushed for 949 yards and led all of college football with 144 points (24 touchdowns) scored in nine games played.

[10] It was also the highest point total scored by a football player in Michigan since Willie Heston in the early 1900s.

[11] At the end of the season, he was selected by the Associated Press as a first-team back on the 1955 Little All-America college football team.

[8][12] The 1955 Hillsdale team was invited to play in the 1956 Tangerine Bowl, but the players unanimously decided to decline the invitation after bowl officials advised that Hillsdale's four black players (Clark included) would not be allowed to play.