All of these places are within a 2 mile radius of MSP airport. The number of reasons to visit MN are unlimited.
Mall of America
The World Of Fish in Richfield. Really cool fish store with over 10,000 gallons of fresh and salt water fish. Probably the most diverse collection of fish in MN. I would guess they might have more species then underwater world.
Water Park of America is a pretty good indoor water park.
IKEA, is across the street from the MOA
The
Minnesota Valley National Wildlife Refuge is about a 1/2 mile from the MOA and is a great place to hike and bird watch. They also have an really nice visitor center with several displays and gift shop. This is one of my favorite places to go fishing and hiking in the twin cities area.
Historic Fort Snelling is also only around 4 miles from the MOA.