Northwestern is probably worth a look. I personally know that Ian Horswill (http://www.cs.northwestern.edu/~ian/) is all-around great, whether you're talking professionally, technically, or personally. But obviously that's mostly relevant for people who'd study in his specific area. I have no particular personal experience with the rest of the university, but its general reputation in CS is good.

It may also be worth considering a bit which aspects different schools emphasize, if she has an idea of which areas within CS she finds particularly interesting. There are significant differences between programs more tilted to mathematics vs. to engineering, for example. Different schools also offer quite different catalogues of higher-level electives, e.g. if you're really interested in AI, the top choices might not be the same as if you're particularly interested in OS development (and vice versa). Of course, it's also okay not to have such decisions made when you're 18.