Well I have as many questions as answers I guess.
First one is, what does SHE want to do? Next, is Ivy League THAT important to HER, or just you? Then, what will she major in?
Of course she is not 'jailbait' at 17. She is at the age of consent. And there are men ALL OVER THE WORLD, not just college campuses. If she is socially/personally educated, she will do just fine making her own decisions about who to or who not to sleep with. That is not really up to you anymore, sorry.
Believe me, I understand how scary those first few realizations are when it occurs to you you can no longer dictate every second of her life, but at 17, she is not REALLY a 'child' anymore, she is a young adult. And a very bright one. At this point the most you can do is cheer her on, support her decisions, and hope you've done your job well thus far.
My oldest went away to college in September at 17, he is very socially immature, but very academically focused. Had a couple nervous weeks, but settled in nicely and finished the year taking 2nd year classes, on merit scholarships with great success.
Next kid is a junior, so the process is starting all over again. He'll also be very young and immature when he goes, but I have complete faith he will acclimate as well as the first.
My 14 year old daughter is already looking at a 6 year doctorate program at Northeastern.
Take a deep breath mom, let her guide you, find out what HER hopes and dreams are (not YOUR hopes and dreams for HER), then relax and enjoy your successful brilliant girl!
:)