It took me a while to put this together, but I put together a plot of high school and college rates in the Midwest (Minnesota, Wisconsin, Iowa, Illinois, Indiana, Michigan & Ohio).
I figured that these states make a good cohort, since they have relatively small geographical counties, usually without significant geographical boundaries between them, and they have a wide mix of agriculture and industry. Of course, as with any grouping, they aren't a perfect fit, but I think they work well enough.
(The picture should probably be clicked on, its a big picture).
After doing all this work, there isn't a lot of new information in this picture. Unlike in the Western states, there are quite a few counties with less than 10% college graduates. I think this might be an artifact of the small geographic size of midwestern counties: Western counties, because of their large geographic size, pretty much have to have certain facilities (such as hospitals) in every county. Midwestern counties, since there are no geographic barriers, don't. That is one possible explanation, at least.
Other than that, there is not a lot of surprises: big metropolitan areas tend to hang to the left, and the top right has four elite counties, three of which are college counties, and the other of which is a wealthy suburb of Indianapolis.