Kazmin stated the defense for teachers clearly and succinctly. It is easier to blame some of our teachers for our poorly equipped students than it is to re-create society's priorities in order to resolve those student needs which are frequently economic in nature.
I have taught at Garfield High since 1956, and I have seen the very same student home problems repeated endlessly. Those who control the real means of needed change turn their heads to more pressing political concerns. Then when industry finally complains that many workers can't handle technological requirements, everyone points a knowing finger at the easiest group to scapegoat and says, "Well, if Jaime Escalante can achieve his level of success, then any dedicated, hard-working teacher can do the same."
The only outcome of that conversation is a defensive and angry core of hard-working teachers who do not see their daily struggles recognized. It is easy to point at some success stories and claim that's the answer. Forget about children who have seen their relatives blown to bits in El Salvador, forget about a girl who has seen her brother murdered by a gang, forget about a child who sees his alcoholic father beating his mom. Because if you look at these problems, then you've got to shell out some money for psychotherapy, group homes for children, clothes for a poor child and birth control for a mother aged 13.