This prof would constantly forget to post important things on canvas which can be really annoying when you're trying really hard to get a good grade in the class. Homework is really hard and it just doesn't seem like he gaf. Somewhat funny but makes everything more complicated than they need to be

He's the one

He is GOAT

The game theory class taken with Karel is really fun, the concepts are explained in a way that's easier to understand, and he's also accessible during office hour (a lot of OH). Though sometimes he would forget to post some important stuff (like homework on gradescope, or lecture notes he promised), but the class is really good.

Very engaging lecturer, great sense of humor. Extremely timely with email repsonses. Grading was homework, 2 midterms, and a final. Holds a lot of office hours. Homework can be tough but he'll help you in OH. Midterms generally easier than homework. Also just a nice guy

HW 25%, 2 midterms 15% each, 1 final 45%; He's very funny and genuinely helps so much in office hours. Favorite math class at UCSB thus far and only class I ever went to that I waNTed to go to because the course content is fun (he makes it fun). Homework was light (5ish problems per week) and if they're hard, mathlab helps so much.

Very nice professor. Lectures were straightforward, exams were very reasonable difficulty. Very manageable class if you study effectively.

One of the best math professors I have ever had. Made all the material easily accessible and genuinely wanted students to succeed. Would absolutely recommend.

The best math professor ever. Lectures are interesting and he posted recordings for most topics from previous years. Grading on exams are super generous. Super helpful in office hours. Respond to emails very fast. Overall great class and great professor. By the way the TA Arthur is amazing too!

Kasteels doesn't make the assessments and content harder than it should be As long as you stay on top of the homework the course will be a breeze. He puts very simple questions on the exam and is very generous in giving partial credits even if you don't get the question right. Plus he's a sexy hot DILF. Who wouldn't want a daddy as their prof?

It seemed like he did not care much about the class and it was clear that he did not want to teach this lower division class. He spent little effort explaining the topic and had no curve at the end of the quarter.

Large class so Prof Casteels wasn't super attentive to individual students but that's what you get in a large lecture hall. HW every week, not too bad if you don't leave it till Sunday night. 2 midterms and a final; go to the lectures so you know what to study for. I failed AP Calc AB in HS over Covid and MATH 3A was far easier for me to learn.

Overall he's not that bad, but he doesn't really give you a whole lot of resources to learn about the topics besides the textbook which is pretty hard to learn from. The biggest issue with this class is the webworks homework. Its really specific on decimal places, and format etc. He also doesn't really define what you need to know very well.

Chill, somewhat funny dude...but makes concepts so much more complicated than they have to be. Learned this math in high school and it was a piece of cake. Casteels makes it so much more complicated by overexplaining.

You can learn a lot in professor Casteels' class, but he does not trick you in homework or exams. So you can learn a lot, and still get good grades.

Took this Spring 2022. Great prof! He won't surprise you on a test with anything you wouldn't be capable of doing, and he curves generously. HW is tough but going to office hours really helps clarify most of it. He responds to emails as well.

Worst professor I've had at UCSB yet. He does not deserve to have a job at UCSB and is plainly the most unintelligent person I have ever seen. lectures are short, bordering on 20 minutes and do not explain concepts clearly AT ALL. Admits that webwork is incorrect but continues to assign unclear problems that are impossible to get right.

Very organizational. Hws and exams are doable.

Nice guy. Good lecturer. His lectures are inspirational and organized. I skipped most of the lectures though.

Great lecturer and he is good at explaining things in office hours too. Reasonable tests and homework, class work is fairly straightforward and easy in general, just go to extra hours and talk to him and the TA and the class will be even easier!

Reasonable tests and homework. Easy, but not so easy it feels pointless. Very straightforward and clear lectures. Wants his students to learn. Lots of help during office hours. Definitely take him, you will learn a lot without much stress.

Midterm2 and Final were hard but he curved the whole class. If you study hard and got relatively good grade during the quarter, he wont be too harsh

Casteels is the only professor I haven't liked. He would mark me down for correct answers in a form not of his preference. I even verified with other professors. Easy material, though. He would shut me down when asking questions not related to the homework or exams, but out of genuine interest in the subject. Everyone else seems to like him, though

Really enjoyed his 108A class. The lectures are well organized and his notes were clear. The midterms were pretty easy and he gave extra credits for the final. Always available during his office hours and even gave extra office hours right before the exams. Great Professor! Definitely will take his class again