I visited Kansas City last September. They have a Gray Line Trolley tour, and that'll give your friends a brief view on Kansas City. It lasts for 1 hour and 20 minutes. It costs $8 or $9, if I remember correctly, but you can get on and off the trolley bus all day after you finish the first round.

The most impressive thing I saw was Hallmark visitor center. Also, there was a museum featuring the steamboat which sank a long ago and recently was dug out. The exhibition was nice. They had a guided tour inside the museum. I'm sorry that I forgot the name.

I think they have many more things to see and do in Kansas City. Following link might help: http://www.visitkc.com/

Satoshi Marui from Tokyo, JAPAN