A 1990 graduate of Northern Vermont University-Johnson, Greenleaf was a four-year starter on the Badgers' nationally-ranked men's soccer team and a four-time All-Eastern Intercollegiate Ski Association (EISA) Nordic skier, earning NCAA Division II Outstanding Freshman honors as a rookie. In 2014, he was inducted into the Northern Vermont-Johnson Athletics Hall of Fame not only for his individual career but as a member of the 1988 men's soccer team.

Greenleaf coached Nordic skiing at his alma mater in 1990-91 and taught 5th and sixth grade for 32 years at Waitsfield Elementary School, earning a nomination for Vermont Teacher of the Year multiple times. He completed a master's degree at the University of Vermont in 2004. Dan is an assistant coach with the St. Michael’s College Men’s Soccer Team.