<p>Speaking from experience, I think it’s actually better to take certain SAT II’s after a non-AP class. In chemistry, for example, the SAT II covers things that are taught much more in first year chem. I took it after taking AP junior year, and had a 730 (not bad, but this is in comparison to a five on the AP test and 800’s on my other SAT II’s and 2350 on the SAT). The SAT II doesn’t cover anything not taught in a class you’ve taken by sophomore or junior year.</p>