Benjamin was an awesome professor. He was super helpful and very approachable/friendly. His exams are pretty hard, but I think he is an exceptional enough lecturer to offset that. Benjamin is the best math professor I've had in math. Here is a full breakdown of this class with Ben:

1) Benjamin assigns long weekly HW sets. Be sure to start early and go to his office hours to ask for help. Homework is worth a lot in his class, too (I think 25-30 percent).

2) Benjamin's lectures are fantastic. He tries to keep you engaged with Zoom polls, etc. He does everything at a good pace and when asked, he is more than happy to repeat himself. His lectures are related to the HW and the exam and can be used as the primary source to learn. I didn't like the textbook for this class, so I used his lecture notes and was fine. His lecture notes are very well organized, as he writes them out during lecture (on pre-made slides).

3) Benjamin's exams are pretty tough. He doesn't test anything that isn't relevant, but he does put a tough twist on concepts you have already learned. Doing the HW helps, but just because you have done the HW, you are not fully guaranteed to do well on the exams. Fully understanding the concepts will definitely help, however. Surprisingly, the average for the exams weren't that bad. The final had a lower average than the midterms (and it was a harder exam as well), but nothing unreasonable.

Overall, Benjamin is fantastic. He really makes an effort to give you the best experience, and during these COVID times, I surely appreciated that. Best math prof. I've had ever at UCLA. Math 135 is supposed to be one of the easier upper divs, but Benjamin changes that. He makes the class harder than most professors, but if you try your best, you will learn something. I would definitely take another class with him if given the chance, but it would be wise to do so with an easier schedule. Nevertheless, this dude is super cool.

Welcome to Math 135! You probably are here because you heard that 135 is one of the "easier" math classes. Let me just say, Benjamin was like "hold my beer", because this is actually one of the hardest classes I took.
Benjamin is a very clear lecturer. We have a Slack page for our class where we can ask questions, and Professor always goes out of his way to answer every question because he cares about us. He does use slides to lecture, but he doesn't just read from them. There are lots of examples and proofs that he works out with us.
The grading scheme is as follows:
29.5% Homework, 0.5% End of the term evaluation, 20% Midterm 1, 20% Midterm 2, 30% Final Exam
>70% guarantees at least a C-, >80% guarantees at least a B- and so on.

The first few weeks of 135 was very straightfoward. All the content up to midterm 1 was simple. But once we started learning about existence and uniqueness, this class felt more like an analysis class than a differential equations class. Half of the class, we were learning proofs and half of the time we were doing computational work.
His homework is pretty challenging and long, so be sure to start early. Homework is due every Wednesday. Each assignment is about half proofs and half computations. The proof questions were very difficult and the computational problems were long but mostly straightforward. Some of these computational problems are very lengthy and you may have to use lots of pages to solve them! Only about 30% of the homework was graded for correctness, and the rest is graded for completeness.
There were 2 midterms for this class. Midterms 1 and 2 were challenging but still had averages in the mid 80s. However the final exam almost made me cry (average was still somehow a 47/60, how??). To put this into context, if you ever played Pokemon, imagine that Midterm 1 is gym leader Whitney, Midterm 2 is Champion Lance, and the Final Exam is Champion Cynthia from Pokemon Platinum. Because that's how hard they were.
To conclude this, Benjamin cares a lot about his students. His Bitmojis make me smile. His lectures are engaging and I would definitely take another class with him again! I highly recommend him if you want to challenge yourself. You will learn a lot from his class!

Edit:
Forgot to mention that I appreciate him giving us 40 hours for the midterms and for curving my 81.8% to a B.