Of the large metro areas, Hamilton County is the strongest in the state (by far). In my Top Academic Ohio High School list, Hamilton County had 31% (22 of 71) of its schools in my top schools list. While Lucas County (Toledo), Cuyahoga (Cleveland), and Franklin (Columbus) had 14% (6 of 43), 17% (17 of 98), and 16% (13 of 80), respectively. These numbers include private and public schools.
I think that much of the success of CPS is due to Walnut Hills. It's a huge incentive for the kids to do well in elementary/middle school.
Cincinnati really "gets" education.
For all of my education data, click here:
http://www.gerberanalytics.com/ogt.html