Right around the hotels is Milwaukee's Third Ward. This area has fun shops, restaurants, bars, and art galleries.
The Milwaukee Art Museum has lots of great art, including some works from Andy Warhol and an extensive Georgia O'Keeffe collection.
Milwaukee is known for its beer and cheese, and the beer Milwaukee is arguably most known for is Miller. They offer daily tours of the brewery that run approx. every half hour (Julia was a tour guide here for a summer and still says it was one of her favorite jobs). The tours are $20 and include a souvenir and beer.
Science museum with freshwater aquarium. They haven't been recently, but Julia says "I'd go back."
Another Milwaukee/Wisconsin staple: Harley Davidson. Julia and Zach had prom here their junior year.