<p>bcon, I personally don't have experience with euro or chem, so I'm not going to give advice on them.</p>
<p>Any AP science class is going to be difficult if you don't have the time/materials to perform labs and get hands on experience. You're missing out on the "fun" of the class, I guess, by self-studying. AP bio is fairly easy though- I thought the essays were a little bit more difficult than some of the others, because science isn't a cut and dry thing, new things are being discovered daily...</p>
<p>APUS on the other hand, is fairly easy as far as history classes go. You don't have to do the APWH thing and go back 10,000 odd years and compare ancient civs, present day civs and memorize some random obscure facts about the ganges river valley. (can you guess which class I'm in now?)</p>
<p>APUS and APWH are graded differently though- APWH is a very cut and dry system. Your essays are graded by a rubric, and based on the rubric, you get a number of points, one through seven. if you hit those first seven points, you can then gain an additional two points based on how well your thesis is, how good your bias is (on the dbq), etc. </p>
<p>On the APUS, it's more...open...for the grader to decide on. There's a rubric, but it's subjective to the grader. So in that sense, it is more difficult, you now have the additional factor of "does my writing make sense to the reader".</p>
<p>MC are easier, I think, on US because the time frame is so much smaller. but that's just my personal opinion, it really is different for everybody. </p>
<p>Good luck on w/ever you decide!</p>