<p>I was wondering if it was possible to go from the 20 series to the 10 series (i am currently in 20A, thinking about taking 10B next quarter if possible)... i have decided to major in general bio and find it absolutely pointless to be wasting my time in the 20 series.</p>
<p>also, does any know if there is a significant drop in the level of difficulty?</p>
<p>Mm, I did this 
20A –> 10B –> 10C</p>
<p>I got a B in 20A even though I worked really hard & I didn’t wanna risk getting any more B’s, so I dropped down to the 10 series and got solid A’s for the rest of the sequence. For 20A, I went to every lecture & discussion and yeah, all I got was a B. For 10B & 10C, I only went to 3 lectures each (for quizzes) & never showed up to discussion. I also didn’t own the textbook till 10th week of 10B. Didn’t really study till quizzes/midterms/final. Oh, did I mention you get to use a calculator for exams in the 10 series? The 10 series is really, a joke. Or at least if you’re decently good with Calculus, you’ll feel that way. My friends used to always make fun of me for dropping down cause it’s so much easier :// Hope that helps answer your question :)</p>