Best teacher I have ever had. Very easy to LEARN from.

Gellar is the best algebra teacher. He makes sure you understand your assignments and works with you. I enjoyed his class alot.

College Algebra. Very straight forward but willing to spend extra time with those who need it.

Great teacher and willing to help.

College Algebra-- Good teacher... if you don't like math he is a great teacher for you! He really makes it easy to understand.

He's early bird that loves to stutter. He only teaches early classes and you have to memorize all formulas or your dead.

Very, very, very helpful. If you have a problem with math he will make you understand. He is very good at letting students know what to study and how much to study it. I recommend him to anyone looking to recieve a algebra credit.

If you want to learn and understand something take this professor.

I loved the way he taught my Algebra 1 class. He was extremely thorough and REAL (which is rare in a math teacher, who never seem to realize that the quadratice formula has no use in real life) about what we were learning.

He is an awesome professor. I took calculus I and II with him. I aced both classes.I guarantee that when you walk out of that classroom you actually have learnt the materials. He puts a lot effort into teaching.He is great and he knows how to teach.

He is brilliant. He ia passionate toward his teaching.Very helpful and you will free to ask him questions.

I had him for College Algebra and Calculus for Business and Economics I. He is very clear when he explains the material and makes sure that everyone understands before moving on. He is a great professor and really knows what he is talking about. He is willing to help anytime during office hours, so don't be scared to ask.

Geller is an awesome teacher! If you suck at math take him cuz he will make you understand it! and he actually WANTS to help you understand it...Plus hes funny! sometimes un-intentionally, but he made our class laugh everyday...and he sounds like Billy-Bob Thorton a little...hehe

He's a good teacher...and pretty much what everyone else said.

The best teacher to take if you really want to learn math. Made calculus less terrifying than it is. you end up leaving the class knowing you learned something.

Hands down, the best math teacher i have ever had. Trig, Cal I and soon Cal II. I thought Cal I would be hard, but left the class an A and B student. Take all math classes with Geller.

His passion shines through his teaching which is hard to come by. If math is not your forte, you need to take him. He's by far the best math teacher I have ever had and I am grateful I have him. You will walk out with a clear understanding of the concepts.

THis professor makes math easy. It can be an intimidating subject, but he makes it smooth and simple to understand the concepts. His test are exactly like the problems you work in class. I have never been so impressed with a teacher. I would take him over again for any class I needed. If you are weak in math, take him,

I had him for Calculus I in the summer. It was a very fast paced course, but he made it as easy as it could be made. Great teacher! Grade was based on 4 tests, some quizzes and a final.

This guy is an excellent teacher; he makes you walk away with BOTH an excellent understanding of the material AND a decent grade, provided you put a modi****of effort. I took him for CalcII, and I still remember all the integration formulas. His teaching has provided a great foundation for CalcIII for me. In short: HIGHLY recommended.

Dr. Geller is a really nice person but his tests were really hard. I'm smart but I'm not a genius and I was getting 65's on all of the exams. I believe that he grades his tests hard and sometimes subjectively. He did make the class alot more fun and interesting. I do believe that if I took another professor I still would have gotten a C. Cute!

Great teacher. Makes class fun with a easy teaching style. Very open for questions and explanations of subjects.

Wonderful professor. Dr. Geller wants you to succeed and will do everything possible to assist you. He has high expectations of his students, so be prepared to do the work. Study, attend class, and you will do well. HIGHLY RECOMMEND him.

Calculus is hard, but he will totally make it easy for you. YOU HAVE TO TAKE HIM FOR CALCULUS I. Before you come to the class know your trigonometry and algebra skills because in all Calculus classes this is important. Remember calculus is basically alot of algebra and some trig. Just know that you are gonna survive if you have those basics :)

Excellent professor! He is enthusiastic about the Calculus and his teaching methods are Crystal clear! Test are a bit challenging though!I ended up making a C in the class, but that was my fault!I learned so much from him! He is a must take professor for calculus!

Prof. Geller is an awesome teacher who makes it abundantly clear that his goal is for his students to succeed. If one teaching method doesn't work for some, he'll attempt other ways to explain it until the topic is understood. I would recommend him to anyone without hesitation.

i love him. he is amazing in every aspect of teaching. and he's cute :)

I took him as an online class but he was always available to answer e-mails. His tests weren't too hard. If you did the homework there were not any surprises. I'm going to try to take him for calculus.

He is super smart, funny and nice. Watch him teaching is a pleasure! His tests are not hard.He is also passionate about teaching and respect students.A great math professor! Strongly Recommend!

By far the best math teacher i have ever had! You will learn so much material but the way he teaches it will stick with you. His test are more challenging but definitely possible. you MUST do your homework, even though he doesnt require it bc it helps with the tests! Take him, you won't regret it!

This class is easy if you go to class and do the homework. I thought that the online labs were actually more difficult than the tests, but he drops your lowest lab grade (4 labs total). He was really nice, and always answered everyone's questions. I would definitely recommend taking him!

Awesome teacher & so nice & funny, the only problem is that college classes are always so rushed :/ In any other subject u can cram & prob do fine but algebra is tough to rush through. Prof Gellar is awesome but with so much material in so little time it's a bit difficult to keep up sometimes. come to class, take notes & study & you should do fine.

Do Take him, he's the best

Great guy, he's a great professor.

Prof. Geller is great. Explains everything very clearly and lets students work in groups. Doesn't move on until everyone understands what's going on. He does a good job of making hard material easier to learn. Tests aren't too hard if you study, though no notecard. Homework is optional.

Great professor, he'll tell you straight forward what you have to and don't have to know. Do tae him. And he's cute :)

He is the Best!!!!! TAKE HIM

what he is good is that he doesnt use mathlab. so you can save $75. Do all homeworks and know how to solve them. then you will get an "A"

I took Calculus 1 in the summer and wasn't prepared for it at all. He is very helpful and animated in class. He wants to help you learn. Know how to do the problems well that he goes over in class. I hated Stewart's calculus book, so I referred to the Larson book quite a bit and it helped.

He is an ok teacher. The subject is very difficult and the lectures are very long. His math lab assignments can be pretty difficult because Mathmatica can be a bit difficult at times.

Great teacher, he always makes sure every student understands the concepts before moving on, and he is great with explaining things if you don't understand.

He is awesome! Do take him!

Easily the best professor I have had at Collin. Geller knows his Calculus and explains it in a way that allowed me to understand. He's passionate and I looked forward to going to his class everyday. Fantastic teacher. You should definitely take him

best professor, He will help you , do take him, i will take him next time. i took online per-cal. you get every week 1 quiz, he give you 3 time to take that quiz, and 4 exam.

Great teacher!! Cal 2 is a hard subject, but he explained everything thoroughly, and tested only an what he taught. He loves math and is a very fair grader. Make every effort to take this guy if you can. One of the best I've had.

Lots of student thinks he is a great teacher, he isn't a great teacher. At best, he is an average to below average teacher. Look, if you are really good at math, then it will not matter who your instructor is because you will do well. However, if you really need someone to teach you, well, Nick isn't your guy.

I'm a high school student taking a college class and he makes it super interesting and not torturous to go to. Better then any of my high school math teachers. If you don't understand he will go back and explain it a different way. He's understanding and nice!

Best Algebra Professor! would take him again in a heartbeat. I failed Algebra the previous year and I got an A. . .math comes easy to me, but everyone else in my class liked him also. If you go to class you should pass. He will stop and explain something again if you need it all you have to do it ASK!!

Very laid back, but that doesn't mean it'll be an easy A if you're bad a calculus. You do have to earn your grade. He is always willing to help and explain and will not demoralize you in any way when asking during lecture. Also, easy to understand! But if you already know your calculus, this class will be a breeze for you!

Prof Geller is a great math teacher. I took him for Calc 2 over a summer semester. He does a good job of simplifying difficult topics. His tests are hard, but are similar to the homework problems. He is a tough grader. He talks about hitting a brick wall in Calc 2. I hit that wall hard... Dont think I made a C.

Exercises are needed. No due homework, he provides selected questions on the book suggests you to do and you can always ask whenever you don't understand. No note on Exams, but do give reviews. No extra credit.

Geller is an amazing prof, probably the best math professor I have ever had, he explains things very clearly and is more than happy to explain things multiple times if need be. His tests are tough but that is mainly because the material is tough, though he is a very fair grader. Great guy cant recommend enough.

GREAT teacher! The best math prof I've EVER had! Explains everything so well, repeats as many times as you need. I had him for Algebra II and wish I had him for Calc. Textbook not needed but lab access is, that's where the h/w is. There's a link to the textbook as an ebook and it's free with the lab. Go to class, do the h/w, and you'll pass!

Very direct teaching style. He has a passion for math and helping others understand it. He is patient and works to make sure that every student gets a concept before moving on. That said, he will NOT just hand you an A. No extra credit, and it's math so any mistake makes your answer wrong; attention to detail is a skill honed in this class.

Great teacher.

I took college math with him, and I was able to understand everything. That's why i decided to take Pre-Cal online. Don't expect reviews for the tests, homework is super essay with videos and examples if you don't understand, test are a kinda though but you have to tries in every answer. The final exam was a blessing, because it was like homework.

He was an awesome professor! Clearly loves math and it's evident in his lectures. Very disorganized, but name a mathematics professor who isn't. Assigns homework from the book; not graded, but still do it! No test reviews, so he takes questions based of that assigned homework. There is NO extra credit, so make sure you study well for the tests.

Absolutely amazing professor. Geller made the "hardest section of calculus" easy. Sadly I ended up with a B because I missed the first week due to personal reasons, but I believe an A would've been achievable. Do the optional homework if you want a good grade. Geller loves to joke around, but he's very knowledgeable.

He's hands down the most amazing calc. prof at Collin. His tests are super straight forward and exactly like his lectures.

hate math & after Geller am considering taking an extra class of his. rare gem of a prof. breaks concepts into bite size pieces. will explain until everyone understands. doesn't rush. no study guides, lays out clearly what to expect. Uses ConnectMath (better than MML). 4 tests plus final. replaces lowest test grade w/ final grade if it helps you.

Geller is great, he makes sure everyone is on board before moving onto the next subject. He will tell you exactly how his test questions will be asked and how to answer them,that is basically the whole lecture, just everything you need to know for the test. Very flexible with due dates, allows you to make them up if missed.

Took Calculus II over the summer with the fear of failing since Calculus has never been a easy subject, especially during summer. Prof Geller is simply amazing, he made difficult concepts easy to understand. He is caring and makes sure everyone is on track. He will answer all your questions, and also tell you exactly what will be on the exams. BEST

This is the professor to take esp. if you are a math major. He invigorates the subject and makes you think. It's a hard class, but with the amount of enthusiasm Geller has in the subject even after 20 years of teaching, the effort is worth it. At this level of math you need to understand what's going on, not just memorize. He will help you do that.

Professor Geller is an amazing professor. I took Calculus II from him and it went really good. He made calculus II fun! He helped me with my problems, and gave good feedback, as well. Just take him!!

BEST TEACHER EVER. If you are taking calc 1 take this professor I promise you will pass. He explains the material so you will 100% understand. His classes are not mandatory, but you will probally not pass if you dont show up.

Online pre-cal was beyond easy. Everything is on Pearson besides the exams. I love how he set up the exams. He just uploads the exam and gives you about 2 days to really work on it and submit it back to him. Highly recommend this class.

This class is amazing and easy!!!! Every homework and lab was on Pearson with unlimited attempts. This course contains 4 chapter tests and 1 comprehensive final. Only 1 introduction discussion. On the test there are multiple choices and a few questions that required you to show work. No proctor and don't have to go to the test center. TAKE HIM!!

Professor Gellar has been my instructor for Calc. 1 & 2. I take longer to grasp concepts so higher math is always intimidating. Half the battle is just showing up. Once you do, he is one of the most phenomenal instructors I've had. When peers are confused, he'll always stop & say "where did I lose ya?", go back and rework in a way that makes sense

Best profesor! Easy grader, caring, and explain things clearly!

Greatest math professor of my life, I took this over the summer cause I needed to finish my math requirements, 5 weeks, it was long work but as long as you took a coffee (class was at 8AM to 12PM) you were chilling. Geller was very caring and made sure you succeed in this class as long as you ask questions if you were doubtful. TAKE HIM!