We HIGHLY recommend doing a Chicago architecture tour on the river! There are many tour boats including Wendella, Shoreline, and First Lady.
One of our favorite places to go for a walk and watch the boats come and go! There are great places to grab a drink or snack and hang out - City Winery, Tiny Tap, Sweet Home Gelato, Island Party Hut, Chicago Brewhouse, and O'Briens
The Lincoln Park Zoo is great (and free!)
The beach is not far away! Head on over to North Avenue Beach or the smaller Oak Street Beach if you are craving a little sand between your toes.