I have a slightly different suggestion. "One Child" by Torey Hayden is the true account of a little girl she taught in the 70's. It is an absolutely heartrending book, but makes you see how incredibly important you are in the lives of your students. (Sheila, a 6 year old, is placed in Torey's class....Sheila took a 3 year old boy out in the woods, tied him to a tree and proceeded to burn him. Sheila was sentenced to a mental institution's children's wing, but due to overcrowding, ended up in Torey's class. There is much, much more) I read the book when I was 11 or 12, and I think that it shaped who I am as a teacher forever. There is a sequel, called "The Tiger's Child" where Sheila and Torey are reunited after a 7 year separation. Torey Hayden has written several books, all based on her personal experiences as a teacher, and they are all excellent. She has only written one fiction novel.
Another suggestion is a little book called, "If the Horse You are Riding Dies, Get Off"- a very short book about standardized testing. Very funny.