I took professor Kellman for psychology 120B - Sensation and Perception. This professor is extremely knowledgeable about the subject and will go out of his way to explain the material thorougly for your learning. He is highly energetic and I can tell that he want his students to enjoy the subject as much as he does. The course can be confusing (especially if you don't know much about the material in the first place). It gets better after the midterm. In order to do well in this course, you must understand the lecture material (use your TA office hours, the blackboard discussion board, and your peers), read the book (this makes the difference between an A and a B), and start early on that paper! Minilabs and discussion attendance are just icing on the cake as they are simple to get full credit for. Overall, this class isn't that bad.