Earl accepted a scholarship to Penn State University where he was the starting point guard on the basketball team all four years. One of the most talented point-guards in Penn State history, Earl battled through numerous injuries in a career that spanned six seasons. A four-year starter and two-year captain, Earl would miss most of two seasons due to injury following his junior season when
he helped lead Penn State to the 1996 NCAA Tournament before
returning for his senior campaign in 1998-99.  

He is one of Penn State's all-time leaders in scoring and assists and he was named to the All-Big Ten Conference second team by the media and third team by the coaches in 1996. He had an injury plagued college career that saw him redshirt twice and spend six years in the program. Earl led Penn State in assists four times. The 1995–96 Nittany Lions team started the season with a 19–2 record and was ranked #9 in the country at one point during the season.

Dan Earl played professionally in Germany, Poland, and Portugal. He also spent time in the Continental Basketball Association as well as the NBA Development League. He got close to making a National Basketball Association team, where in the 2001–02 and 2002–03 seasons he spent time with the New Jersey Nets during their training camps.

In 2006, Earl joined his alma mater as an assistant coach. He spent six seasons with the team until 2011, at which time he became the associate head coach at the United States Naval Academy when Ed DeChellis became the head coach.

He is currently the head coach of the Virginia Military Institute, taking that position on April 12, 2015.  Dan and his wife, Sheila, were married in the summer of 2008 and are the parents of two daughters, Mila and Alyssa.