<p>You can NOT cancel individual subjects; cancellation process for subject tests are by sittings meaning you can cancel only by the date you’ve taken the test. So if you took the three SAT IIs and wanted to cancel one of them, you’d have to cancel the other two as well.</p>
<p>The proctor should have a form that you can fill out if you want to cancel the score there; also, if you want to take one just for fun, then just take one and don’t take the other two. That won’t penalize you seeing it’s lenient as to whether you undertake the number of the tests or you overtake the number of tests you registered for. You can also take a different test than what was registered as well!</p>
<p>I suggest (if you want fun) try taking a foreign language test; how about Japanese or Korean? ;)</p>