<p>APs are lovely lovely things; the least useful credits are US History (only counts for me as random humanity credit) and English (still have to take an English class, but if you get a 5, you can take more advanced classes, like Shakespeare, instead of Interp and Arg, but I kind of liked my Interp class anyways). If you get credit for something, you <em>probably</em> can skip and go to the next class (like if you get 2 semesters of calc credit, you can take multivariate or diff eq), the exception being economics.</p>