While researching I looked up different ways of getting us to Chicago.
One Way from Kansas City, MO to Chicago, IL= around $62.00
Round trip= $125 (split 3 to 4 ways for each car load)
One Way ticket= $48.00-$58.00
I'm assuming it would be double that for a round trip
According to Orbitz the cheapest round trip flight ticket would be on AirTran for $339
(probably not a pick)
CTA/PACE-In city transportation
Parking in Chicago can get expensive so if we ended up going we would probably want to purchase a CTA/PACE 7-day pass which is a $28.00 pass to get on the trains and buses around the city and to avoid paying $3 an hour for parking (or however much it gets around there). Plus if we use the pass enough, it's definitely worth saving on gas money too.
Let me know if I missed anything and I can research some more!