First impression someone might have of Dr. Chang is that he goes really fast from the start. You can never seem to be able to put your pencil down (unless he uses slides for at most a week or two). The class pace sped up to the point where we finished the curriculum a lecture or two ahead. What I liked about Professor Chang though was that he was straight-forward. Organic chemistry is a hard enough subject to grasp and how Jonah specifies what to study helps with the learning process. His two midterms and final are DOABLE, especially since he provides the exact same structure of these in the practice papers he gives before the exam day. My advice to anyone who has to take a course with him: definitely keep up. Rewrite the rushed notes you take; do the optional homework, digest; make flashcards for the reagents and mechanisms; and regurgitate the practice exams he gives. Then you should be good. Aside from that, Jonah is a really humorous man and gives a refreshing perspective to learning in lectures.