When Atticus lectures Scout about talking the way everyone at school does, she responds that if school is such a bad influence he should not send her there.
To satirize something is to make fun of it. Satire is social commentary mixed with humor.
The incident with Atticus and Scout is funny, because Scout still does not like school, ever since she got in trouble for knowing how to read when she started school in first grade.
Despite our compromise, my campaign to avoid school had continued in one form or another since my first day's dose of it: the beginning of last September had brought on sinking spells, dizziness, and mild gastric complaints. (ch 9)
Scout finally decides that the best way to avoid school is to pick up a swearing habit.
I was proceeding on the dim theory, aside from the innate attractiveness of such words, that if Atticus discovered I had picked them up at school he wouldn't make me go. (ch 9)
Atticus knows that she is too smart for school, and that is why she is miserable. Yet even though the people at school seem to be hopeless at educating Scout, Atticus still has her go. He knows that she will pick up a thing or two other than illness and swear words.
A school is a microcosm of the community. The children will act as they have learned from their parents. Scout can only learn how to get along with people if she experiences them at school.