– Architectural boat tour is the #1 thing people like as tourists, at least in my experience. Make sure you book with the Chicago Architecture Foundation tour, not one of several competitors.
– The Art Institute is probably the third greatest art museum in North America. If you like art, it will make you very happy.
– For free, you can walk around all the parts of the big lakeside park across the street from your hotel. The Art Institute is in the middle of it, the Field Museum and the Aquarium and Planetarium at the far south end, but it also has Millennium Park, with some wonderful monumental modern public art that people love, and the Frank Gehry-designed Pritzker Pavillion, and Maggie Daly Park (a gigantic playground), as well as beautiful formal gardens. And Lake Michigan. It’s one of the nicest urban parks anywhere.
– Chicago is a great place for trendy dining. Anyplace I recommended now will probably be passe by April. (But you might be able to get a reservation for April.) Actually, I don’t know what’s trendy now. Ask someone else.
– Chicago also has great music of all varieties, and great theater. Not just Hamilton, or Broadway tours, which is generally what you will find in the Loop… Lots of repertory companies all over the city doing seasons. And improv comedy (heard of Second City?).
Down in Hyde Park, in addition to whatever University of Chicago tour you take, you can see the Oriental Institute and the Smart Museum (both UChicago museums), and see if you can get a tour of the Frank Lloyd Wright Robie House. Also, bookstores – the Seminary Co-op in its glitzy new home, and Powell’s.
The food in Hyde Park is not something that would draw you from anywhere else in the city, but if you want a smidgen of bona fide UChicago culture, you could go to The Medici (OK, nice atmosphere, a common take-your-parents place), Valois (sort of diner/cafeteria with breakfast, lunch and dinner 24-7, and until the past decade or so a chance you would run into Barack Obama), Rajun Cajun (half-Indian, half-Cajun), or Harold’s Chicken (makes KFC look like health food). Or one of any number of Asian restaurants of all varieties along 55th or 53rd Streets (the only one I’ve tried is Snail Thai; it was fine). Or the local Giordano’s location (if, unlike me, you don’t think deep dish pizza is an abomination).