Are you working in a part of Chicago and living in a part of Cincy where flying is actually worthwhile? For me, something like this might come down to whether I was working downtown vs. somewhere near ORD. Could also depend in which side of Cincinnati I lived on, although I know less about that bit...

Midway doesn't appear to be an option (to CVG, anyway).

My guess is that fare-watching and just booking the best rates is *probably* going to beat AAirpass. Being predictable Fri-Sun, you could jump on a fare sale and buy 5-10 trips at a time.

Since you're doing this repeatedly I wouldn't advise the hidden-city trick that I imagine most Cincinnati people are well aware of. The fly-to-Indy-instead idea is kind of pointless unless your job is pretty much *at* ORD...

No idea whether the student discount idea is still a thing...or how closely it's limited to current students. (I remember using student fares in Europe in the 1990's but rarely see it talked about in a current domestic U.S. context.)