An identical twin born in Fort Worth, Texas, Robbins grew up primarily in Breckenridge, one of three sons of football coach Cooper Robbins, Sr.[3][4] Along with twin brother Ron, he graduated from Breckenridge High School in 1952, where his father was the head football coach for seven seasons (1945–1951), then became the freshman football coach at Texas A&M in 1952, and son Don played for him that first season.
[5] After two seasons in El Paso, he was hired as an assistant at Idaho in April 1968 under first-year head coach Y C McNease.
[6][7][8] When McNease was dismissed after spring drills in May 1970,[9][10][11][12] Robbins was promoted to head coach of the Vandals.
[15][16][17] He was succeeded by Ed Troxel, an assistant under Robbins and his two predecessors (and the head track coach).
[18] Robbins returned to Big Spring High School as head coach and athletic director in 1976.