Chofetz Chaim fits the criteria that you’re looking for. I’m not saying that the limudei chol is amazing, but they prepare the boys for the regents and they give APs, too.
What everyone is saying about a cult is 100% true, though. If he does get sucked into the system, he will most likely not want to leave. However, Chofetz Chaim does allow (but does not encourage) boys to go to college at a certain point. I personally have dated two Chofetz Chaim boys who were taking Landers classes; both of them were serious learners, not yeshivish, mentschen, and well-rounded intellectually. Trust me, they were not using overly yeshivish lingo.