The smug girl is often seen in the background in Bart's classroom and around Springfield Elementary. Her face usually carries a slight smirk. Her hair is usually colored red or brown, but it is occasionally other colors. She has never spoken. She was at the Springfield Elementary Science Fair, but did not enter anything.
Her real name has been hinted at. It does not begin with "A" as Edna Krabappel says there are no A’s in her class (despite the existence of Adrian Belew). However, her last name is close to the front of the alphabet. When Bart's snake Strangles is let loose and they ask everyone to get in line in alphabetical order, she is closer to the front.
Behind the Laughter
Being a background character, her appearance has not been finalized so her hair color often changes dramatically between episodes, though it is commonly brown.
She wears a green T-shirt, a blue jacket, pink jeans, and white sneakers. She has a smug expression on her face, as well as curly brown (sometimes red) hair.