"To bisect a line it is divided into two equal parts," she writes, adding a diagram, Jorsling does not explain any of the notes she writes on the board.
Keith, the redhead, jiggles a red pencil between two fingers so it looks like it is made of rubber. Khalilah spreads the Boston Herald on her desk.
When the class does geometry problems from the textbooks, Khalilah figures the angles in her head, shouting them out before the others.
When she finishes, she starts to read the Herald again. "I always read the whole paper," Khalilah says.
"It's not called for for someone to get shot every day," she tells me in an urgent voice after math class. "It's not going to solve anything..."
English. Mr. Kaufman, with a moustache and a soft voice, has been teaching this extra class all year; the regular teacher has been out with heart problems, he says.
"It's not that easy to do, to step in and develop a curriculum for an entire year at a moment's notice," he says.
Khalilah takes another vocabulary quiz here. Fill-in-the-blanks include questions like, "The dog bit me when it got--(vexed)," and "Don't rush. Go nice and--(leisurely)."
Kaufman is torn between making the test harder, to raise students' expectations, and making the test easier, to give them self-esteem. Usually, he makes it easier, he says.
After the test, they tell a story aloud, pretending to be Guatemalan Indians from Rigober la Mencho's autobiography. They each contribute one sentence at a time, following each other's lead.
For a few minutes the class flows. Egged on by Kaufman's questions, Rinaldo describes an Indian's drunkenness; Erik says he got drunk because he was depressed, but Khalilah says he was depressed because he was drunk all the time. He should have been supporting the family, not getting drunk, Khalilah says.
For lunch she eats a bag of Lays Sour Cream and Onion potato chips and a half slice of pizza from the cafeteria. The pizza costs one dollar. Splitting it is cheaper, she says. Khalilah says that is her usual lunch and it is filling enough for her.
After school Khalilah usually goes to track practice for a few hours. Wilma Rudolph, the track star, is her hero. Then she goes home and to the Walter Denny Teen Center down the street, "so we don't get in trouble on the streets."
"I don't spend my time doing nothing," she says. "Time's too valuable to waste standing on a corner, guarding turf...that's just stupid."
Khalilah refuses to be distracted from school by the vices of society. Teachers say it's because she has a supportive home environment, while Khalilah Horton says simply that getting in trouble would be self-defeating.
"Lots of people aren't active," she says. "I tell them not to smoke and drink around me, because it's just not cool...you lose your chance."
And Khalilah, whether or she ends up at South Boston High School, does not want to lose her chance.
The music teacher does nothing to prevent the class from replacing the classical cassette with a rap tape of their own.