It's too bad you're not getting a little more time in. I personally really enjoy the Field Museum and the Art Institute of Chicago. The Museum of Science and Industry is also very cool. Then again, I've only been to Chicago a few times, but those are places I have been and would go again. As for Wrigley, I've only been there once, and I had a decent time. I enjoyed the history of the park, but the game watching experience was just ok in my mind. But, I'm sure that it's going to be a fun experience for you and your kid. I wish I could recommend more to do around the stadium, but from what I remember, there were a lot of bars around the stadium, which probably isn't much help.