Relevant Law:
MCL 28.425o (CPL Free Zones)
(1) Subject to subsection (5), an individual licensed under this act to carry a concealed pistol, or who is exempt from licensure under section 12a(1)(f), shall not carry a concealed pistol[/u] on the premises of any of the following:
...
(h) A dormitory or classroom of a community college, college, or university.So you cannot carry CONCEALED in a college classroom (or dorm). However, note that the preemption law only expressly prohibits local governments (defined as cities, villages, townships, and counties -- not universities or school districts, etc.), so it's unclear if the universities are preempted from creating their own rules.
It is my understanding that nearly all of Michigan's public colleges and universities prohibit self-defense rights EXCEPT for Michigan State University. MSU's rules are that they will only enforce state law:
http://trustees.msu.edu/ordinances/ordinances_sec18.htmlSo it appears to me, and I am not a lawyer, that you could openly carry in classrooms and dorms at MSU (as well as the rest of campus).