First of all, let's denounce the first comment as I agree with the second comment:
- "I would argue that the aspect of 'support' comes from the fact that the extensive homework (which is due at the end of each week, making it manageable if you start early) actually allows you get in lots of practice."
What are you insinuating? That those who do argue that the homework is extensive are lazy? You do realize that we have other classes to attend, other essays to write, other homework to complete for other classes right? Completing 50 guaranteed to 58 questions per week and studying for the weekly quizzes is too much. Forget about the discussion work, as we only have to do some of it to get complete credit. Fix your diction and tone.
- ". . . he will take so much time out of his week to not only give extensive office hours to those struggling, but to craft study guides for midterms and finals that really prepare you for the exams. . ."
Almost every professor creates study guides. Come on now. Be realistic.
- "Jukka is the type of person to check in with you and tell you to not worry when you're stressed. (He actually cares about you as a person!)."
This person is just boosting at this point. He doesn't check in with you when you're stressed.
- "He gave us an extra credit opportunity to make up our midterm grades."
He basically had to because after the midterm, students swarmed to him asking him to curve it or make a make up one. He also reached a bunch of emails. So "gave" or was "obliged," which is the better choice?
Closing statement, this class will take a whole lot of your time. I have no idea what the first person was on. If you like learning from slides and NEVER seeing a problem being solved by hand in lecture, this is the class for you. If you like to have to go to discussion just to see problems solved by hand, this is the class for you. Essentially, this was a class to support us but no support existed. No hate to the professor, but his teaching methods are not it.

To the new Bruins who sucked at Math in HS/did not do great on the placement exam,

You will do great in this class. This class was far easier than LS 30A this quarter.

Jukka provides an immense amount of support in this class and genuinely wants to see all of his students succeed. He will do his best to make sure you understand the concepts presented in lecture & will make himself available to ensure your success. He offered online office hours twice a week, in person student hours twice a week after lecture, and individual appointments if you ever asked. If you do not understand a concept, the resources are there to help you.

About the class in general:

Lecture sessions involved a slideshow with participation iClickers - correct/incorrect answers did not matter. You got the iClicker points as long as you participated. He will discuss the proofs behind the famous trig limits/power rule/etc, but you don't need to know any proofs for his tests. If you really don't want to show up, make a few friends in the class & have them tell you when the iClicker is coming (not that I condone skipping lecture - I did not skip lectures).
Lab session involved a weekly quiz starting Week 2, followed by a lecture on whatever he felt we needed help with. Quizzes are extremely basic problems (2) about concepts from previous week's HW. As long as you did the homework and checked your answers with the solutions he posted on Monday, the quizzes are easy points.
TA sections involve a worksheet, 5-6 problems, relating to a concept he taught in lecture that week. My TA spent 20ish mins each section re-explaining the concept on the worksheet, and then you had the remainder of the time to work on the worksheet. If you don't want to come to the discussions, there is no penalty, but you are responsible for the worksheet, due Sunday.

Workload:

HW: 40-60 problems due at end of weekend each week. Gave whole class extensions to Monday afternoon, multiple times. If you turn in the HW late, admittedly the course readers never enforced the 10% late penalty (half my HWs were late). You do have to put in effort & show work, but HW grade is based on complete attempt at problems, not correctness. Yes, the HW takes a lot of time.... don't always start on Sunday like me.
Worksheet: As stated before, worksheets were 5-6 problems, and you only had to do ~50% of the worksheet to receive full credit for it.
Post Lecture: There is a post lecture question graded on correctness to assess your understanding due at the end of each lecture day. There is also a post lecture, 1-2 sentence reflection on what you learned that day. Takes under 5 minutes to do.

Midterms/Final:
He gives practice exams and detailed study guides for each midterm/final, detailing concepts, specific questions he assigned relating to said concepts, and exam format. Jukka literally has a paper in there telling you HOW to study for the exam (what to do, in what order). He also hosted office hours going over practice exams/midterm/final content.

Practice exams were just like the actual midterms/final, down to question format and everything. He gave away the second midterm on a silver platter by giving "hints" on each question and by asking the minimum/max of a function... and then showing the graph of said function afterwards. Class median on midterms/final was 87, 92, and 85. That should tell you all you need to know.

I took the time to do this whole writeup because of the previous reviews. If you failed Math 31AL this quarter, one of the following is true:
- You need to speak to CAE
- You need to reconsider the attitude/effort you approach school with
- You need to fix your study habits

I believe Jukka is a great teacher. If you fail this class, it won't be because of him or his tests.

Jukka is probably the best professor I have ever had at UCLA. His lectures are engaging, he clearly loves teaching, and he provides the most academic assistance I have ever seen from a professor. He holds multiple hours of office hours every week and hosts two review sessions before each exam. He is very adamant on ensuring that all students in the class do well and are actually learning the material as well. If I could take another class with Jukka, even if it's not math, I definitely would.

tl;dr: Jukka is the goat

Keranen is an absolutely amazing professor. There's no reason to hesitate when picking Keranen. If you can take him, DO IT. Decently easy A and you also learn a lot.

Really good and passionate professor. I think he was one of the best professors who motivated me to do things for this class. His grading scheme is very forgiving, and i would definitely recommend for a class like this. He has a lot of office hours that are available, his midterms are just like he says they are and its just a good class to be in. I found this to be a useful class.

Jukka is the best mathematics professor I've had at UCLA, and is in my top three across the entire school. He is extremely well-prepared, does a great job explaining the complex topics brought on by an upper-division linear algebra course, and has a wonderful personality. He holds several office hours each week, including one on Sunday and extra review sessions before exams, to help assist with the weekly homework assignments and to answer questions about the subject matter.

Each of our two-hour lectures opened with an extensive review (sometimes taking up to a third of the total class time) of the previous material to make sure everyone was staying up to date and following along. After that, we went through two slide decks with a short break in the middle. The slides were published the evening before so we could prepare before coming the next day. After class, our one-hour discussion section went over some additional practice problems in order to get some hands-on work with the material. At the end of each day, we needed to submit a class reflection, detailing the new content we learned and giving us an opportunity to recall everything so that it stays fresh.

The class was not too difficult, but it also did require quite a bit of work. Even though the class is condensed into six weeks, rather than ten, we still covered every single slide that would have been presented in the ten week course. Jukka helpfully left the last unit (on inner products) off the exam to give us a chance to study for a full week.

We had one midterm exam, attendance was required, and the biweekly discussions had a worksheet submission. There were ten homework problems a week, not taking more than a couple hours in total.

Professor Jukka is by far the best professor I have ever had within the two years of college so far. Before enrolling in his class, a lot of my peers have offered very positive feedback about him and his reviews on Bruinwalk was also very assuring. However, it was my experience in this class that I realized how amazing of a Professor he is and how helpful of a resource he becomes for us students.
Beginning of the summer session A, I met with him and discussed about dropping out due to the difficulty of the class; however, he reassured me and offered to take time out of his day to meet with me for a tutoring session to help make sure I understood the class materials. Not only did he went beyond his ways to help me, but he was very communicative and held many, many review sessions and office hours to answer our questions and make sure we were fully prepared for the exams.
Additionally, Professor Jukka is great at teaching the course materials as he's very clear and goes at a good pace for everyone to understand. Unlike some professors I've taken, he's willing to make sure that no students fall behind and that they can be comfortable to ask any questions.
I am truly thankful that I got to enroll in one of Professor Jukka's class because it was very eye-opening and I am very, very appreciative of his unwavering support to make sure his students succeed in his class. Without him, I would have most likely dropped out of Math 115A and probably struggled worse with another professor so I am truly grateful for Professor Jukka. He is an amazing professor and individual and I hope to be able to take more upper div classes with him in the future and I hope many students can experience the wonderful learning experience that I got with Professor Jukka.
I know he can't see this but I want to thank him very much and that words can't describe how grateful I am. The UCLA Math department is very lucky to have a professor like him and I wish him the best of luck!

OMG where do I begin?!?! Jukka will be the best math teacher, if not the best teacher you've ever had. Words cannot explain how terrified I was for Math 31A and he completely eased my worries within the first week. The COUNTLESS review sessions for the Midterm and Final also show how much he wants us to succeed in the class. He told us he sleeps 3-4 hours a day and it's literally because he works so hard for us :(. I will say, this class is a LOT of homework (up to 80 hour-long problems in a week), but it's all extremely helpful in understanding the material. Be prepared to dedicate most of your life to this class when you take it, but I wouldn't have had it any other way! If you fail the class initially (calc is sooo tough), Jukka will give you the opportunity to take an oral test with him through Zoom (basically a giveaway). He's the sweetest and he deserves the WORLDDDD!!!!! I also want to say that this was my first calc class and my math skills are absolutely horrifying. So if I can do it, you can too! Take advantage of office hours and tutoring (my PLF was a miracle)! and you'll do great :)!!!!

Jukka is the -best professor. Take him and you don't have to worry about one single thing.

Take 115A with Jukka. He has an awesome personality, clear lectures, and straightforward tests with LOTS of officer hours and review sessions. I got a C in 33a and didn't remember much about linear algebra but that didn't matter. Jukka starts fresh and makes it alot less intimidating. Attendance was mandatory but I didn't even mind going to every one. The small classroom size also completely changes the dynamic for the better.