I used to live in Decorah, IA, and visited Rochester for shopping at the Apache mall as a kid. You are not going to see a ton of cultural stuff there but I hear the art museum is decent if small. The rec center is also popular.
The spam museum is usually pretty popular as well.
If driving is something you can do, the twin cities are approx 90 mins north. If you are able, and you don't mind the weather there are some good hiking trails in the area too.