Law and Economics was one of my favorite classes at Columbia. Elliott Ash is a great lecturer. He's organized, dynamic and structures the lectures very well. He posts the slides a day later, so you can (and must) review them while solving problem sets and studying for exams. They are the key to the class. He explains topics in a straightforward way and his lectures are concise and challenging, but not in an overwhelming way. There were extra readings such as articles and excerpts from papers and books that were useful and relevant for the topics discussed. I really liked how he incorporated real life examples (through extra readings) into his lectures. It made the class very engaging and interesting. The summaries of math notes that he would explain in class first and then post on coursework were very helpful for the homework problems, I feel like I learned a lot.
Elliot is also incredibly approachable and patient. He answers all questions asked during and after class, and responds to e-mails instantly. Also the atmosphere of the class was very relaxed and friendly.