The other reviews for Professor Yao all say it already: she's incredible, definitely one of the most efficient, funny and engaging teachers I've ever had. I P/NP'ed this class because it wasn't a requirement for my degree, but had it been a letter grade it would've been an A-. The emphasis in her classes is not getting everything right but rather trying your best, and it shows in how she doesn't grade assignments punitively. She even canceled a couple of assignments this quarter to take it easier on us. I'm going to be honest, this class does have a heavy workload but it 100% pays off because it's excelent practice. Her sense of humor kept me going this quarter and I'm sad I probably won't get to take another class with her again.

About the grading:
> 15% participation
> 20% homework assignments
> 10% quizzes
> 35% exams (one on week 5 and another on finals week)
> 20% oral exams

I will admit I had my regrets before the quarter, because I wasn't sure if this class was worth it (it really messed up my schedule for the quarter), but after taking this class, I can confidently say that it was 100% worth it. 姚老师 is an extremely effective, engaging, funny, and considerate professor, and is someone you can really relate to, especially since Chin 4A typically has a pretty small class size, so you have this nice classroom environment.
Lectures usually involve slides, talking about new vocabulary, grammar forms, and talking about the textbook passages and also cultural facts, which is really cool. You're learning more than just the Chinese language here, but also history of some of the words, Chinese culture, and you might even hear some of 姚老师's own life stories and experiences. Each lecture begins with some sort of quiz (vocabulary quiz on the textbook passage on Tuesdays, sentences quiz on the textbook passage on Thursdays), or if you don't have a quiz, you have some sort of examination (whether it be written or oral). Make no mistake, this class is a lot of work (as learning any language should be), but it's really fulfilling and well worth it in my opinion. Don't be afraid to make mistakes during lecture, because it really helps you improve your speaking and thinking skills, and due to the small class size, you won't be worried about embarrassing yourself in front of hundreds of students. Lectures are often extremely funny, engaging, and we can talk about all sorts of stuff, to the point where it truly is like a "discussion" instead of a lecture. In fact, her class has been one of the few classes were I looked forward to going to lecture everyday, and learning something new about Chinese.
The grading breakdown is 10% Participation, 20% HW/Essays, 15% Quizzes, 35% Written Exams, 20% Oral Exams. There are two written exams (one midterm, one final), and two oral exams (one with the midterm, one in week 10 before finals week), as well as four essays throughout the quarter. Don't be scared by making mistakes, as this is a class where you can learn, make mistakes, but still do pretty decently in terms of grades (if you're truly worried you can take this class P/NP if needed). Yao won't hesitate to mark or correct something that's wrong, but as long as you're showing effort and truly trying, you'll still get a good grade, as she takes off like 0.1 points for each mistake. For one of my essays, my entire paper was red from her remarks, but I still made out with the grade from that paper, so it shows that as long as you're trying, you shouldn't be worrying about your grade (she's very lenient in grading). Written tests are just like any language exams, and our oral exams consisted of giving speeches in front of our classmates, and we had a lot of creativity in choosing our topics.
If you have time, I highly recommend visiting her office hours. Not only is it a requirement, but you also get 1-2 hours extra per week just conversing in Chinese about literally anything, and it's a good experience to sharpen up your speaking skills and learn more about the professor, yourself, and your fellow classmates.
Overall, I cannot stress how much this has improved me as a Chinese speaker; I came in with only basic conversation skills (and frankly probably couldn't read a Chinese newspaper), and I come out having given an oral presentation in Chinese and writing academic essays. While I still can't read everything, it shows me how much I've got to learn but more importantly how far I've come to get to this level. This class has given me the inspiration to continue in the 456 series, and I truly believe if you're sincerely interested in learning Chinese, this is one of the best bets you can make, no regrets!

The BEST professor on campus. She is a 2nd year Chinese professor for the A Track (A Track is for native speakers). I thought I was pretty good in Chinese, having taking it throughout high school and every saturday but after one week in Yao Laoshi's class, I realized how much the other Chinese teachers I've had sucked and there was so much I still needed to learn.

I encourage every A track students to continue with this professor (even if you have already met the foreign language requirements). I entered the class still unable to read a Chinese newspaper article and came out fluent enough to write an academic essay in Chinese and have an adult conversation w Chinese professionals.