<p>I already posted many things about IIT - but I'll add one thing </p>
<p>The math isn't all that difficult. To be sure, it's not a joke, like the SAT math tests. But it is a lot like the AP Calculus exam, with a few more advanced topics. It's not extraordinarily hard, and far, far from actual olympiad question difficulty.</p>
<p>Certainly, if all US high school students were required to take such a test, there would be quite a few who would do well.</p>