Green attended John Harris High School (now Harrisburg High School) in Harrisburg, and graduated cum laude from the University of Iowa with a BA in finance. According to Green, he was planning to be a high school teacher if his football career didn't pan out. In college, he started as halfback in each of his three seasons with the Iowa Hawkeyes, playing under coach Ray Nagel.Iowa City Press-Citizen, December 25, 1969 (all-Big-Ten honorable mention for Green). In his collegiate career, Green had 139 carries for 699 yards and nine touchdowns. His best individual game was in a 1968 loss to Texas Christian University when he rushed 18 times for 175 yards and two touchdowns. After graduating from Iowa, Green briefly played professionally for the BC Lions of the Canadian Football League in 1971.
