@ucbalumnus . I do not really know how exactly they were prepping but maybe it was not a cram. Maybe they just tried to teach kids math and English around SAT test. It was 2 days a week, Friday and Saturday and he would get some homework. Every Saturday they would write a full timed test and then analyze it. He could probably clear 2100 without this prep. His school is considered a peer of Stu and TJ but it is not all STEM. Very competitive to get in. I later learned that hagwon had a prep course for the admission test for a very affordable price of 3K (now 5K).
Not sure about the value of IB program but I saw that he read Nietzsche, Chekhov, Karl Marx and a bunch of other interesting literature. Sounds like fun but did not help with English grammar.