Marguerite is pretty embarrassed for her and her grandmother's sake and in my opinion it shows how much Marguerite would like her grandmother to be more like Sister Flowers. She even goes as far as to say that she "hated her [grandmother] for showing her ignorance." This helped me to understand how highly Marguerite regarded Sister Flowers and how much Marguerite would like to be like Sister Flowers.
Mrs. Flowers has a little talk with Marguerite and tells her, basically, that lack of education does not mean a person isn’t intelligent.
She said that I must always be intolerant of ignorance but understanding of illiteracy. That some people, unable to go to school, were more educated and even more intelligent than college professors. She encouraged me to listen carefully to what country people called mother wit. That is those homely sayings was couched the collective wisdom of generations.
Education separates people, but something more important unites them - self-respect and respect for one another. Just because Marguerites grandmother intelligence is passed from one generation to another, it shouldn’t go on unnoticed because she can also learn something from