Originally Posted by DarcyMae
*I'm an art, architecture, and history lover (The only must-do on my mind is to see the Art Institute.)
If you're serious about the architecture bent, then you ought to very strongly consider taking one of the Chicago Architecture Foundation tours. The number available is staggering, so you shouldn't have any trouble finding one or two that meet your interests.
http://www.architecture.org/tours.aspx