The Kansas City Temple Open House is going on now until this Saturday. Mapquest claims that it's a 2hr. and 50 min. drive from West Des Moines to Kansas City, but we usually find that Mapquest is a little on the conservative side.
I know several people who have gone to this, and they all had the BEST things to say about it. It's a wonderful opportunity to show your kids the temple while they are young, since they won't get many chances like this.
You do have to make a reservation (although, I doubt they would turn you away at the doors).
Click here for more info.