Women in engineering varies greatly by the major. I was an EE and there were very, very few women. Computer engineering had more women, Civil even more and Chemical had probably the most at my school...Mechanical? Almost none. Every school has it's specialty, too, so it would help to know what direction she would want to go.

I specialized in RF/wireless engineering because that was what my school was known for and it has since served me very well. Now I recruit for my company from the top RF/Wireless schools and I can tell you, that the top schools in engineering in general do not even make our list as the top schools for our specialty...so school choice/program choice can matter quite a bit. She can get top education at non-top schools (for less than top dollar!) if she can narrow down her direction. Thought I know this is asking an awful lot of an 18 year old (I surely wouldn't have been able to make that choice back then!)!

As far as the best programs for women, I will mention again that it can really vary by major. I definitely second the recommendation to check with SWE (Society of Women Engineers) as they have chapters in every engineering university in this country (and many internationally). If they track this, they'll be a great resource.