<p>I signed up for the Physics and Math II tests to take in May. However, I'm taking AP U.S. History and I just got the Direct Hits book that targets both AP and SAT II. I think I've heard of someone taking a different test than the one they signed up for once, but can I take the U.S. SAT II at the test center without changing it on my online form and having to pay the fee? I used a fee waiver for the sitting so would I have to pay, or would I even be allowed to do another test?</p>
<p>Also, would it even be worth it to take a third test, especially because I'm majoring in science/math? The most prestigious schools I might apply to are Cornell and Carnegie Mellon.</p>