Lots of college educated Chicago residents seem to leave town when their kids reach school age, and there are lots of possible reasons for why this happens more in Chicago than other places. The real question is what we can do to change this situation, so that college-educated parents stay (and even move here) rather than leaving town.
Thirty percent of Chicago area residents live in Chicago proper, and 30 percent of central Chicago residents are college educated, but only 16 percent of Chicago residents with college degrees are parents with school aged kids -- a much steeper dropoff than other big cities like NYC, LA, or even Milwaukee. All this, noted by Chicago Magazine's Whet Moser, is nothing new to most of us. Moser ticks off the usual suspected causes -- lack of sufficient numbers of "good" schools and an overly complicated application process. ("I can imagine that some people move to the suburbs just to make the process comprehensible," quips Moser.)
Let me throw in a couple of additional possibilities for which there is no conclusive evidence but seem possibilities: (1) a series of efforts to improve low-performing schools and build a handful of amazing new buildings (under Vallas and Duncan in particular) that left the gentrifying middle-performing neighborhood schools in the lurch, (2) the much-admired (and -maligned) local school council system which was never really robust enough to allow parents and teachers to take real ownership of their schools in terms of money, programming, and hiring (and was, frankly, already asking quite a lot of unpaid volunteer council members), and (3) corruption, waste, and bloat in the education system and other parts of the city government that have remained a presence despite steady improvements.
Anyway, who cares? The real question is how to change the system so that things get better for everyone, including middle class parents -- not to take focus away from current CPS kids and schools but to pursue a dual strategy. I've come up with various hare-brained schemes in the past -- a gentrification czar, transitional funding for neighborhood schools going through decreases in poverty funding, a unified application system (like the one they have in Denver), diverse charters. But I'm sure you have better ideas and am counting on you to share them.