Alexandra is Scout's aunt. She is a woman who trusts in the traditions of family and the society that the family lives in. She believes in the roles that men and women should play in society. She does not think Scout is a lady and she doesn't believe Scout is very clever because of Scout's personality and the way she dresses, like a tomboy. Scout does not like to do "girly things," and this goes against everything that Alexandra believes in. Scout is bright though. She learned to read at an early age and she is very intuitive. She can see into peoples hearts and has an excellent social IQ, she just chooses to live her life the way she wants it to be. Adults are not always correct in the way they evaluate the cleverness of young people. As a teacher I am supposed to be able to tell about how clever a child is, but I have been wrong. Our beliefs and value systems, especially as adults, often interfere with our judgement.
"a conservative woman concerned with social and class distinctions and bound to the traditions of the South. She tries to counteract her brother's liberal influence on his children by reminding them of their family's eminence and by trying to make Scout behave in a more ladylike manner."
Scout isn't dull, but Scout just doesn't like doing things that are girly like Aunt Alexandra would prefer. She is actually very smart and learned to read when she was very young. She was pulled down by her teacher because she could read early and this went against the conservative view held in the town.