The Question and Answer section for Flannery O'Connor’s Stories is a great resource to ask questions, find answers, and discuss the novel.
I'm sorry, there is no actual teacher in the story. Grandmother might be considered a teacher for the younger members of the family, as her memory of the glorious south is one she shares with them. In context, this would make her a history...
The first stop is at The Tower for barbecued sandwiches, where the owner, Red Sammy Butts, and his wife wait on them. Later, Grandma convinces the family to take a detour on a dirt road that leads to an old plantation.
What particular story are you referring to?