Due to her being over 70 years old, Kelly was prohibited by the Michigan Constitution to seek re-election in 2012.

In late 1956, Marilyn Jean Kelly moved to Ypsilanti to begin undergraduate coursework at Eastern Michigan University; she received her B.A.

Following a brief stay in France, wrapping up her graduate studies at La Sorbonne - the University of Paris, Kelly spent five years teaching French in the Grosse Pointe public school system, Albion College and Eastern Michigan University.

Marilyn Jean Kelly also served on the Michigan State Board of Education during the 1960s; later elected as President of the statewide organization.

In 1971, Marilyn Jean Kelly graduated with honors from the Wayne State University Law School.