McCallum won Indiana High School Athletic Association Championships in both his junior and senior year at Muncie Central High School. At Ball State he scored 2,109 points during his career and was Player of the Year in the Mid-American Conference his senior year. In 1983 he was awarded the Frances Pomeroy Naismith Award, which is an annual college basketball award in the United States intended to honor shorter–than–average players who excel on the court despite their size. He was drafted by the Indiana Pacers in the 8th round of the 1983 draft with the 164th pick overall. His jersey (10) is one of two numbers retired at Ball State, along with Bonzi Wells's 42.
McCallum's coaching record at Ball State was 126–76. He guided the Cardinals to two NCAA appearances during his tenure.
National champion Postseason invitational champion Conference regular season champion Conference regular season and conference tournament champion Division regular season champion Division regular season and conference tournament champion Conference tournament champion