Meet the SAT tutor to the 1%

But his finely honed -- and expensive -- methodology could be in flux now that the College Board plans sweeping changes for the college entrance exam.

Among the changes: Test takers will no longer need to commit scores of obscure vocabulary words to memory, and math sections will focus much more on real-world problem solving. College Board president David Coleman said the changes, beginning in the spring of 2016, aim to level the playing field for those who can't afford pricey tutors and classes.

So what about Green, who's built a business around that uneven playing field?

Over the past nine years, he's cultivated a strategy in which he observes each client one on one