In the US, always look for a coupon!
Chicago is famous for its architecture, get a 2 for 1 adult coupon for a Wendella Boats Architecture tour cruise for 90 minute at this site <– click there. Saves you $26 (one adult ticket is $26)!
The tour guides are experienced, informative with a good sense of humour. Highly recommended. There are many boat cruise operators, but Wendella is a local family owned business so it is a sustainable travel choice! Support the local Chicagoans!
Enjoy the cruise and tour!