<p>The 17 series isn’t worth it, imo. I think it’s a weeder course for bio majors, personally. 
Harder than 17 series without the perks of the 21 series. Yeah, you get Bio applications… but really? It’s just an unnecessary headache if you haven’t taken calc before. Final for Spring quarter – saw friends staying up until 4 AM (with an 8 AM final) because they didn’t get a portion of it. Not cool.</p>
<p>Take the 21 series if you’re confident in your math skills AND have taken calc before. It’s hard, but it’s worth it – I wish now I had taken the 21 series because it keeps your options open, which is the most important thing! :]</p>
<p>I took the 16 series. Definitely the easiest classes I had my freshmen year. If you had a great Calc teacher, you will be fine. Definitely drifted off in 16A, 16B, and part of 16C until we hit 3D shape-volume-thingmajigs (yes, your high school calc knowledge WILL get you that far). Easy A, great way to de-stress, annnndd… yeah. Gives you some buffer during finals week as well – winter quarter, had 2 finals on the first day (without a dead day!), and 16B acted as my buffer – used that time I didn’t study on 16B for Chemistry. LOL. :]</p>
<p>It’s really up to you. But I’d recommend the 21 series, simply because you might doublemajor in Physics.</p>