Tola lives in a run-down block of apartments in the megacity of Lagos, in the country of Nigeria. She lives with her grandmother, who is very bossy; her sister, Moji, who is very clever; and her brother, Dapo, who works very, very hard. Some say that more than twenty million people also live in Lagos. There are billionaires with private helicopters to take them to Mecca every Friday. And there are people with no bank accounts. If they miss one day of work, they cannot buy food that day. Tola and her family are lucky. Tola''s brother, Dapo, has a job as a mechanic.

And they can buy as much food as they need! Dapo earns so much that Grandmommy does not need to work selling groundnuts by the side of the road like she used to do. Now Grandmommy can stay at home and chat with the neighbors who live in the other rooms in the block of apartments. And now Tola can go to school every day instead of having to help sell groundnuts sometimes. Tola loves school! And when she comes home, there is always food ready. And food is even packed for Mrs. Shaky-Shaky too. Mrs. Shaky-Shaky is a neighbor who is too shaky to cook for herself.

So Grandmommy often packs food for her. All the neighbors do. "Come and eat," Grandmommy says to Tola every day when she gets home. "Eat and then you can concentrate on your schoolwork." And every day Tola hugs Grandmommy. It is so good to eat. So good to have time for homework. One evening, Tola opens her math notebook.

She loves how numbers fit together like a puzzle--a puzzle that you can put together and then take apart again. She stares at the pages where she has written her times tables. And suddenly, Tola sees the answers to division problems! "Moji!" Tola shouts. Tola''s sister, Moji, does not look up from her borrowed school computer. Moji has a scholarship to a fine-fine school. She is determined to become a doctor. Grandmommy says, "Tola, do not bother your sister!" Grandmommy is determined that Moji become a doctor too. Then they will be able to live in a proper house with several rooms and have a cook and a washerwoman.

But Tola is too excited to be quiet! Inside the equation 3 x 12 = 36 she can see the answer to the problem 36 ÷ 12! And also the answer to 36 ÷ 3! Tola is sure of it. She shrieks and claps her hands. Moji frowns. "What is it?" she asks at last. "Multiplication and division are the same!" Tola crows. "But backward!" Moji smiles. "Show me!" she says. So Tola writes: 3 x 12 = 36 36 ÷ 12 = 3 36 ÷ 3 = 12 "You are right, little sister!" Moji smiles again.

She looks up at Grandmommy and says, "Maybe this one could get a scholarship too!" Tola''s eyes become as wide as the pans Grandmommy used to fry groundnuts. Could this be true? But just then somebody starts shouting in the corridor outside their room, and Grandmommy hurries out. "A scholarship, Moji?" Tola asks with her eyes still wide. Dapo laughs. He is resting on the bed after his long day bent over the open hoods of broken cars. "What is it with you and school?" he asks. "Other girls like to think about fashion and hair and boys and babies--" Moji snorts. "It is you who likes to believe girls think about fashion and hair and boys and such because you want girls to be pretty and think about nothing but you!" she says.

Dapo''s mouth opens and closes like a fish. Tola giggles. "But you know nothing about girls!" Moji concludes. Dapo narrows his eyes, but before he gets the chance to speak, shouts come through the open window. "Da-po! Da-po! Da-po!" Dapo smiles and swings his legs down from the bed. He leans out of the window. "How far?" he asks. "Wha''s up?" "We are losing!" a boy shouts back.

"I beg, come play for us!" shouts another. Dapo laughs. "I work now," he says. "I tire too much to play football." There is a chorus of disagreement. But Dapo shakes his head again. "I cannot play now," he says. "I am the man of my house.

" Dapo turns away from the window--just in time to see Moji roll her eyes. "Wha''s your problem?" he asks. "Man of the house?" Moji says. "You are only fifteen!" "So?" Dapo sucks his teeth. "Who paid for that phone sitting next to you?" Moji used to be the only one in her class without a phone. And the other girls mocked her for it. When Dapo found out, he had worked overtime for weeks until he could buy a phone for Moji. Moji stares down at her phone now.

She bites her lip and says, "Sorry, Dapo." Tola''s mouth falls open. She has never heard Moji apologize to Dapo before! "No problem." Dapo beams. He is grinning as if he has just won Nigeria''s Got Talent !.