<p>Thanks so much for the responses. </p>
<p>I guess what I was trying to figure out is - say, I want to simply "sit in" in a class - take it neither S/U or C/NC just AU i.e. audit. Why I want to do that is a different story.<br>
I've heard of graduate students doing this. If they feel background from a certain class would help, they just "sit in" and take the course for audit.
I was just wondering how that would impact tuition. And based on the discussion, I am also wondering if at all undergrads can do this.</p>
<p>It was helpful to know that C/NC and S/U are not the same things. Thanks!</p>