Chicago Rocks!
Being from Chicago one tends to take things for granted....there are the obvious museums, sporting events, etc. I tend to always suggest a tour of the Brookfield Zoo. It is an award winning zoo, very large and "animal friendly". The primate house is a huge open area with large "trees" and tropic rain storms to mimic their natural habitat. Birds fly around free.. anyway, you get the idea. It's an easy trip down 290 W and follow the signs! Or use the Metra train system. The Shedd aquarium is also great. Also, for really upscale dining, try Charlie Trotters, but make a reservation in advance.
Have fun!
vurban1