<p>I am registered only for the math level IIc test but i want to take the writing test and the physics test standby.is it possible ? do i have to bring with me that registration letter (the one that people who do not register by internet use ) ?</p>
<p>You don't have to take them standby. All you have to do is walk in, take whichever tests you want to take, and leave. You don't need to tell your proctor. You don't need to call the Collegeboard beforehand. You don't need to fill out any special paperwork.</p>