Going to Wrigley Field is a religious experience. Make sure you schedule so the Cubbies are in town, and by the looks of things we should be pretty damned good this year. Tickets are easily had if you are willing to pay for it. They will be sold out, so going to a ticket broker or scalper will be your only choice. You might want to spend some time on Craigslist before traveling. Do your very best to get seats in the sun, it adds to the experience. Keep in mind that game days are simply chaotic up there and there are literally dozens of bars big and small surrounding the stadium. Things get a little rowdy post-game so be prepared.
The Museums are all world class. The Field Museum, Art Institute and Shedd Aquarium are all collected close to one another and you can walk through Grant Park and Millennium Park while commuting between the two. You could do them all in one day if you got started early, though I personally think that would be a little bit of an overload.
The Museum of Science and Industry is a fave and it’s huge but it’s a bit off the beaten path. It’s on the south side, about a 15-20 minute cab ride from the loop, close to the University of Chicago so you could group those two together.
Evanston and Northwestern University are north of the city, but not impractically so, and you can take the Red/Purple Line to get there. A trip up there would make for a nice morning jaunt, you could shop and walk the campus and settle in for a nice little lunch at a cafe if it’s warm enough.
Oak Park is another key location just outside of the city easily accessible on the Green line. It’s the center of many of Frank Lloyd Wright’s best known work and there are several tours to look into. It’s another half-day trip, so you will have to consider how much time you have to spare.
In the city, there’s an endless list of things to do. If you are able to score tickets to Wicked I highly recommend it. It’s one of many first rate musicals and shows available. Most of these shows are located downtown in the Loop. The Loop isn’t really known for being a destination aside from visiting the Sears Tower, especially on the weekends when it can be pretty quiet. Some of the best architecture tours are the Boat Tours which circle the Loop via the Chicago River. Just being on the river amidst all the towering buildings is a pretty terrific experience, there isn’t really anywhere like it.
Blue Man Group is always an entertaining and unique way to spend an evening and it’s located in the North Halsted neighborhood, popularly know as Boystown, which is a huge gay community. It’s pretty affluent and happening so if that’s something that interests you you could make a short trip. It’s adjacent to the Wrigleyville neighborhood on the north side, only a $10-15 cab ride from the Loop.
Steppenwolf is famous for the actors it’s produced and always has some of the very best dramatic plays. Right across the street is the Royal George Theater which is known for it’s comedies. Both are located on the south edge of the Lincoln Park neighborhood which is a very affluent residential neighborhood with some of the finest dining in the world. Both Alinea and Charlie Trotters are within a couple blocks walk and there are 6 or 7 other nice restaurants right there on Halsted. Lincoln Park also contains DePaul University which makes for a really great mix of young and middled aged people and feeds a really dense network of sports bars and casual dining. The Halsted and Armitage intersection is home to one of the best boutique shopping areas in the city. If you get a block off Halsted and walk up Dayton or Orchard on either side you can see some really amazing single family mansions on quaint tree lined streets. The neighborhood is bounded on the east by Lincoln Park (the actual park that gives the 'hood the name) and the Lake. It will be dense with runners, bikers and sunbathers in the summer and contains some great botanical gardens and statues. Lincoln Park Zoo is settled in here as well, it’s free and open every day.
The River North area which lies between the Loop and Lincoln Park/Old Town is where you are liable to send most of your time. It’s the core tourist/hotel area because of it’s central location. This is where the famous Magnificent Mile is located. All the best known stores have flagship stores here and every luxury hotel has a location on the strip. Take your pick, if you’re savvy with Priceline you can get a great rate at a 4-star place, the regular rack rates can be $300-$500 a night. I suggest stopping into the Drake Hotel for brunch or afternoon tea. It’s pricey but it’s a really indulgent experience and makes you feel like a titan of industry without having to actually be a millionaire.
The John Hancock Building is on the Mag Mile too so you can step into the observatory or the Signature lounge on the 98th floor. Both the Hancock and Sears Tower observatories are cool, so take your pick. The Hancock is a little cheaper and conveniently located. It makes for a nice little quick trip to take a break from shopping. The Sears Tower is located in the south loop and it’s tour is a bit more elaborate with history and all, it was the tallest building in the world (still is when you eliminate superficial spires and antennas) so that gives it a bit more gravitas than the Hancock. Still, if you are limited on time and don’t want to make a special trip and don’t want your hand held by a guide the Hancock is a excellent compromise.
River North is home to all the best known restaurants. Hundreds upon hundreds of places to eat, Italian, Pizza, Steaks, Sushi, Ethnic, French and everything in between, both upscale and casual. Giordano’s is my personal recommendation for deep dish 'Za, while Gino’s East, Uno’s (and Due) and Lou Malnati’s are other choices. Each is a little different and people have strong opinions on which is better. Gino’s is the best known and unfortunately the most disappointing, I generally assume that tourists who decide they dislike Chicago pizza went here instead of the superior Giordano’s or Malnati’s. I’m sure someone will come by and totally disagree with me soon.
There are lots of other interesting neighborhoods but frankly you won’t have time to see them all. Bucktown/Wicker Park on the northwest side is a favorite among the hipster/artsy crowd. It has plenty of little boutiques and galleries. It also has it’s share of bums and slackers which some people think adds to the edgy coolness. Personally, I think it’s overrated but I’m not into the whole tattoo-piercing-starving artist motif. If you like small independent art galleries it’s worth your time though. Lincoln Square is even further northwest and is a nice up and coming area with a real German heritage and lots of food and drinks. Andersonville is a very popular and diverse area on the far north side. The West Loop is just west of the Loop (obviously) and is a fast growing residential area ripe with cool loft buildings, the meat packing district and plenty of restaurants. This is where the famous Greektown section of Halsted is located and is worth a dinner or lunch reservation. You could couple this with a trip to the Sears Tower since they are somewhat close to each other if you choose.
Anyways, there’s lots more and you can’t see it all in a single weekend but I hope this is a good start. Also you might want to do a search for previous threads on the topic, we’ve done this several times.