University of Kansas clocks in at $29k for four years; UIC in Chicago is about $25k (plus some fees that might bring it closer to 30). UMN does appear to be pretty expensive relative to other schools for in-state tuition, but it's a quite reputable school so maybe they've earned a premium.
Hm. When I look at UIC's tuition calculator, it's giving me
$6757 per semester for undergrad engineering tuition and fees per semester. Over 8 semesters, that's ~54K. Other departments are slightly cheaper but all were over $6K/semester.
That's more time than I really wanted to spend on this topic, but I do find it interesting that even state schools can cost way more than I would have suspected.