 After graduating from SIUE in 1997 with a Bachelor of Arts degree in physical education and kinesiology, Margenthaler served as head coach at Roxana High School in Roxana, Illinois and as an assistant to SIUE Cougars women's coach Wendy Hedberg from 1997 to 1999.He worked as an assistant to head coach Paula Buscher at Bradley University, 2000–06, then from 2006 to 2011, he was an assistant to Lisa Stone at Wisconsin.On April 14, 2011, Margenthaler was named the head women's basketball coach at SEMO.