Go out and play, attend a PG showcase or tournament. Get a qualified evaluation from a scout, or coach who can identify true talent, not based on height. If you have what coaches like, you will hear from them, though they may not be who your son is interested in.
Keep working hard, in the classroom, in the gym, on the field. Start making contacts through emails.
If your son becomes a true P5 player, he will get noticed.
However, your son should ultimately decide where he wants to get his degree. Not just who he wants to play for. As far as the Ivies, RJM is correct, too early.