I wouldn't even know what math is if it wasn't for Mr. Chang.
He is a very good teacher, despite his changing moods and strict attitude. His lessons are thorough and will help you in future math classes in college.
I complained about him when I had him my senior year, but I wish more of my math professors in college are like him. He is really good, and prepared us so well for AP test. Sure he gets on your case, and is mean if you don't do hw, but explains things well.
He kind of has a temper, but he has a lot of good teaching skills and he's pretty good at making you understand the material.
I took his class Stats back in 2002. Just study the homework and get into a good group quiz group (it makes a difference), and you'll pull an A easy.