Land of Lincoln Awaits --- to be found all around you
While you are in Springfield some things not Lincoln are good too. There is a water park and amusement center in Springfield Knight's Action Park. Route 66 Drive In and the State Fairgrounds are open during the summer. The Illinois State Fair is in August.
A Prairie Style home now owned by the state is available to tour. I found it a thrilling experience. 201 East Lawrence
The Illinois State Museum is worth a visit while in Springfield. 502 South Spring
So mix history and fun in one day or over a couple of days but do take your family to Springfield. You may find yourself asking for book after book on Lincoln. Still trying to capture your sense of Lincoln, the man, the legend, or the secular saint.