Cliff Harrison went from Walpole High School, where he helped them win a Massachusetts State High School Championship in 1945, to Dartmouth, graduating in 1951. His only international appearance came on the 1952 Olympic team. At Dartmouth he centered a line with the brothers Joe and Bill Riley that was the most prolific in collegiate hockey history, scoring 209 points in 23 games. In both 1948 and 1949, their Dartmouth team went to the final of the NCAA tournament, but lost in the final both times. Harrison led Dartmouth in assists in 1949-50 and 1950-51, and in scoring in 1950-51, and was named first-team All-America in 1951. His 84 assists in his college career are still a Dartmouth record.