One of the more reasonably priced hotels in the area is the Days Inn, Bridgeview, approximately 12 miles from campus. You will need a car. Days Inn
If you are flying into Midway Airport and renting a car, or even if you are driving into Chicago, the hotels near Midway Airport are about 10 miles from campus. You will need a car. Hotels near Midway Airport
There is also a Ramada Inn in the Chicago community of Hyde Park, home of the University of Chicago. There you would be within walking distance to a commuter rail line to the CSU campus, about seven miles from CSU. Hyde Park Ramada
The landmark Congress Plaza Hotel is located downtown and is convenient to the commuter rail line to the CSU campus, and Grant Park. It is just south of the "loop." Congress Plaza Hotel
Also south of the loop is the Travelodge. It is reasonably priced and near the Congress Plaza Hotel.
The gorgeous Hard Rock Hotel Chicago is very pricey, but is a short walk to north Michigan Avenue, the commuter rail line to the CSU campus, and the Architecture Foundation boat slip for the excursion. If you can't stay there, you might want to find something near it. It is located downtown, north of the "loop." Hard Rock Hotel
You may wish to check out hotels.com for more Chicago hotel options.