Your son’s story sounds familiar. I applied to a couple local safety schools. I also took a couple of shots at a little more prestigious schools. Not Ivy caliber. Accepted to one and wait/denied at another if I remember correctly. Some great suggestions like a Grinnell.
Coming from a disadvantaged background it was “I didn’t know what I didn’t know” about college life, how to succeed and use the many resources that schools offer. That’s where these smaller schools outshine your large public schools unless you get into a good honors program. Good luck.