<p>The non-academic differences are much greater than the academic differences. </p>
<p>For starters NYC > Chicago > Philadelphia. But NYC $$$ > Chicago $$ > Philadelphia $. And Philly is a much more student-oriented city than NYC or Chicago, where they could really care less about students.</p>
<p>Penn sports >>> Columbia > Chicago. Penn has a much bigger greek scene than either of the others. Columbia has less campus activity because NYC really sucks people out of the campus. Penn is much closer to fun stuff in Philadelphia than Chicago is to fun stuff in Chicago. At Columbia, most people live on campus because it's cheaper than anywhere else that's convenient and reasonably attractive. At Penn and Chicago almost everyone winds up off campus for at least their last two years, because there's lots of cheap, attractive, convenient housing.</p>
<p>Penn has twice as many undergraduates than Columbia or Chicago, with more diverse specialized interests. Penn is much more pre-professional in character than either Columbia or Chicago; Columbia meaningfully more so than Chicago. A quarter of Penn students go to Wharton; Columbia is in the financial capital of the world; Chicago (the city) offers business internships aplenty, but the business/financial environment is way more low key than at Penn or Columbia. Chicago doesn't have an engineering school; Columbia and Penn very much do. Chicago and Penn both have world-class hospitals and medical research facilities right on campus; at Columbia, that stuff is a subway ride away.</p>
<p>Penn, of course, has no core curriculum, and not too many general education requirements. Columbia and Chicago both have really strong, time-consuming cores. The Columbia core is completely one-size-fits-all, which means every first year is doing the same thing at the same time. Chicago is more like a limited Chinese menu (one from Column A, one from Column B . . . ), which means its core can be sculpted to individual tastes more, but provides less of a common experience for everyone.</p>
<p>Beyond that . . . the universities are really comparable academically. X department may be slightly better at one than at the others, and vice versa, but the academic quality (of students and faculty) is really not a point of distinction. </p>
<p>Columbia seems way more politicized in a nasty way than Penn or Chicago. Because Columbia thinks of itself as the top university in the center of the world, it has the delusion that what happens there matters, which means people grandstand a lot, and outsiders get involved, to the detriment of free academic discourse. Penn and Chicago are both more chill in that regard. Chicago has a strong intellectual conservative tradition. The students at Penn are probably more politically conservative, on average, but at Chicago the liberal-conservative debate is constant and very respectful, and almost no one hews to some defined party line.</p>
<p>Finally -- Columbia and Penn are 90 miles apart on the East Coast. Chicago is in the midwest. That makes a difference to lots of people.</p>