The University of Minnesota scenes are meant to take place in either the Minneapolis or Saint Paul campus.

In season 1 (Episode 6, I think.  I'll verify later.), there's a shot of a sign that says "College of Biological Sciences".  Only the Twin Cities branch of the University of Minnesota has a College of Biological Sciences specifically named like that.  CBS has buildings on both the Minneapolis and Saint Paul campuses; I was unable to identify any of the buildings seen in the show.

It's possible they faked the building signs and shot them in Toronto like most of the series.  If so, they did a pretty good job of matching the [U of M's sign style][1].


  [1]: http://signs.umn.edu/pdf/TC_SignStandards.pdf