Joel is very unorganized and he never responds to emails within a reasonable time frame. He is forgetful of which topics he has taught in previous lectures. He has a mandatory attendance policy but he misses quite a few days himself and DOESN'T email his students the morning of. This class is not not an easy A; it requires a lot of busy work.

Very organized; expectations clear. TA's were helpful. I did not want to take this class, but I learned a lot of useful business math and business applications for Microsoft.

Attendance required. I-clicker quizzes every class period. Labs are really easy but time consuming. Joel likes to cancel class and not tell anyone. A bit hard to understand bc of the way he speaks into the mike. The material is very useful to anyone in any major. He uses his own textbook/lab book. The tests and final are easy.

Joel makes it very clear what is expected of you in his class. The final was very easy and so were his quizzes in class. A few classes were canceled and they were all announced on WebCT prior to class.

Most of his lectures strictly powerpoint, but always well prepared. He sometimes will put you on the spot during class to get everyone involved. Overall very fair and I learned a lot. He's a nice guy and will give you all the points he can especially if you follow up with him

I did not want to take this class but it was required. It started way too easy for me, but there were students in the class who needed the basics. Things got more interesting as we moved on. As long as you actually do the assignments, you will get an A. He is very clear about expectations - do the assignments exactly as stated!

Projects are clearly defined. All you have to do is go to class, go to lab, and do the labs. Tests are straight from labs. Starts too easy, moves to pretty useful business concepts. I use the information from this class a lot now that I'm in the Business School at UNM.

Ok, I failed this class last year because I was too dumb to just do the work. Now I'm acing it. It seems too easy and he's picky, but now that I'm doing the work, I get it. This really is good stuff if you are going to be a business major. Boring, but important basic stuff.

Joel is easy to work with if you do what he says. Sometimes he shows the class e-mails he doesn't return. Man, some people don't even tell him what section they are in or what their name is. Do the work, go to office hours if you are not getting an A, and stop whining.

Its a hard class if you make it hard, just get the labs done, show up for his boring lectures and get easy quiz points, and thats all. Lab instructors normally help pretty good too.

If you can't pass business computing taking it from this guy, god help you. Helpful (give specifics though) and good at picking helpful people to run his labs. Easy points for attending the lecture, and only 2 exams plus the labs. You have to take it, might as well take it from him.

Very detailed assignments. Starts very easy, really basic, because some students are at that level. Moves to pretty advanced concepts by Thanksgiving. At first I thought this would be a blow-off class and I was taking it just because it is required. Now I'm glad I'm in it; I'm learning a lot that will be useful in my business degree and career.

Straightforward. Not an exciting lecturer, well prepared. Very helpful if you go to his office hours, less so if you e-mail him. You cannot do the assignments the night before; you have to keep up. I'd take him again.

I've had Joel for 150 and now 152. He is a more interesting lecturer in 152, probably because it is actually programming and not B-school prep work. Assignments are still pretty clear, and he is always helpful in office hours. This is a harder class than 150.

I agree with the previous raters; if you do the work, you'll get the grade. He's not exciting in lecture (come on, it's Excel!) , but he's really available in office hours. What more do you want?

Joel is awesome, honestly one of my favorite classes. Very knowledgeable about Java and very interesting. I am looking forward to having him again. He is sarcastic, and can come off rude, but if you know his sense of humor it is not meant maliciously. I definately recommend him.

Joel was a good instructor. This class would be better as a hybrid course (which it will be next semester). If you are good at setting up easy alegebra level math word problems, you will do fine in this course. Things get a bit tough towards the end (IF statements) but other than that this was an informative course.

Great class; great prof. I had no programming experience before taking this class and Joel showed how it could be used for my field (film). It wasn't easy, but he is very fair. I went to his office hours two weeks before each project was due and he was really helpful. Don't go the day before. Everybody is there and that is too late to get started.

Excellent course. I found Mr. Castellanos very interested in students' success - especially when I showed interest in my own success. He does expect you to be an adult; you have to do the work and come to his office hours in a timely fashion if you need help. He will not baby you or cut you slack when you are lazy. Great class for business school!

This was my second computer programming class. It was a lot of work, but it was all very relevant and provided good practice in real programming. Joel was available in office hours, less so by e-mail which seems strange for a CS prof, but okay. Not for people who aren't interested in CS or who expect to go to lecture and get an easy A.

There seems to be extreme bifircation in these reviews between people saying Joel is great and awful. I suspect the difference is in CS/Engineering majors and business students. In CS, you really have to work. You have to spend hours outside of class to learn what is taught; it isn't spoonfed, multiple choice work. Joel is a very good CS teacher.

Mr. Castellanos went well beyond Excel in this class; he taught many different business principles including finance and accounting information. I am very glad I took this class. He is very specific and very detail-oriented. You cannot snooze and turn in work at the last minute. I think this will be very useful in my career as an accountant.

Good class; organized with labs that force you to practice the skills taught in lecture. Very detailed grading makes it easy to get an A; if you take the time to follow instructions you will get an A. Material is all important for business majors of any area. I use this information every day.

Joel's office before tests. I think he was very good and that what he taught is very useful. He never laughed at any of my questions and I was starting kind of behind because I did not have a good high school.

You will learn a lot of material, but it will be boring. Grading, quizzes, and assignments are fair.

Joel is awesome! Really understands the material, assigns great projects that force you to learn the material, and is just a funny guy all around. Usually you have a project every week, but the bigger ones you usually have 2-3 weeks to work on them. Super helpful during office hours and always willing to help outside of them if he has a second.

Is his class a breeze? No, definitely not. But I like his class all the better for it. When you take his classes, you come out feeling like you've learned something, and his labs and projects are the perfect mix between challenging and fun. If you're at all interested in computer science, his classes are well worth taking.

Required for me to get in to the Business School. Class started boring and too easy, but is very detailed and useful right now. Joel has little patience for people who don't do the work or who ask for help without trying things themself first. Otherwise he is very helpful and spends as much time as you need explaining things.

Joel is a great professor and if you have any questions he is glad to help you. However, he isn't the easiest teacher and if you take no initiative in your learning you won't get much out of the class. He won't seek you out to help so you have to ask him.

He expects students to work and learn. His assignment write ups are modeled after the real world, meaning they are vague. Yes, he will tell you what he expects the end result to be. But leaves getting up to that point up to you. If he is in office, he will stop what he is doing and help you if you ask.

What you will get for your programming assignments is what he expects the end product to behave like and a tip here and there, and a detailed explanation on new concepts. If you need help and he is in his office, 9.99 times out of 10, he will help out even if you ask outside of Office Hours, he is even there late Friday nights.

My first programming class - and I wasn't sure that I could do it. I didn't always understand assignments, but Mr. Castellanos was always available in his office hours. I put a lot of work into this class and I learned a lot. I will take more programming classes because of this course.

Very helpful, and fair. He tells you how he wants the end product to be, but leaves getting up to that point up to you. He will help you anytime, and cares about all his students. But he does expect the students to be adults, he will not hold your hand like High School.

very eccentric guy, but really passionate about coding. You really have to rephrase your questions bc he's one of those professors who "won't answer stupid questions". I thought it was a really basic and easy intro to coding with python. The TA's are your best bet for getting proper help on assignments

Great professor who is very passionate about the material and truly appreciates when students show initiative. That being said, don't take his class if you are not willing to put in the effort. I skipped prerequisites, so this may not be the case for others, but I spent an average of 30 hours a week on solely this class (you could get by with less)

Professor Castellanos expects everyone to do their share of learning. I received an A+ in his course and I had no CS/Programming experience. His assignments are alterations from the book. If you read ahead, start the assignments on time, and ask questions you will do just fine in this class.

I learned a lot from this class, but I also worked my a** off. If you think you can skip class or get by only going to class, you are going to fail. This class - and other CS/math classes require you to prepare ahead of time (read the book!), go to class, and then work on the assignments. I also had to go to Mr. Castellanos' office hours.

351 is tough no matter who teaches it. Joel is energetic, passionate, and helpful - if you ask him. This is a class that you can fail if you don't start early, work hard, and ask for help. I think Joel is one of the better teachers for it, but just know that it is tough. It definitely prepares you for a job when you graduate.

I've never taken any kind of computer programming before, and this class kicked my butt. Mr. Castellanos worked with me during his office hours and my TA helped me in lab. I still had to read the assignments ahead of time and again afterwards to get all the information. This is not a class to sit through or to just try to cram at the last minute.

This is known as a killer class in CS no matter which prof is teaching. I found Joel enthusiastic about the material, and a bit disorganized in his lectures. However, the programs we wrote were tough and real-world. This class has prepared me more for the job market than any other class I've taken at UNM. Take it and work hard!

Large Programming is known as "the reaper" at UNM - and it doesn't matter who teaches it. This is a tough class. You've got to write very large programs as part of a team - very similar to real job stuff. Joel gives wide parameters - like a real client - and expects you and you and your team to figure it out and make it run. Good Luck!

If you have never coded before, you are of course going to have a tougher time than others. But Joel is an entertaining lecturer who in my opinion, broke down the basics of coding pretty clearly, and moved along at a fair pace. If you pay attention to the lectures, read the textbook, and ask any and all questions you have, then you'll be fine.

Joel comes of as mean and an awful professor, but that's not true. His class is difficult but you'll be able to pass as long as you attend lecture and lab. He is an extremely smart man and sometimes he forgets his students aren't at the same level he is. He's very helpful once you get to know him and he is a lot nicer than he appears.