Tonight, people swarm into the Harriet Tubman Learning Center on West 127th Street for the organization’s annual gathering, pushing past security guards and a vendor with pins that declare, “I ♥ being God.” Supreme mills about in the foyer, greeting old friends with tight hugs.

It is a muggy night in Harlem, but the children do not care. They savor any chance to visit. ■ This is the place where, a decade earlier, Chanel and Supreme fell in love. They have returned over the years, pulled by the Five Percent Nation, the movement spawned 50 years ago by a contemporary of Malcolm X who broke from the Nation of Islam.

And yet summer, no matter how stifling, also carried a certain promise, the kind that comes of chance encounters on the street.

As the days grew hotter, Dasani and her family remained stuck in the same miserable room at Auburn.

School was winding down when the children learned that their only other refuge — Grandma Sherry’s rowhouse in East New York, Brooklyn — had gone into foreclosure. Sherry could end up homeless as well, at a time when New York’s shelter population had surpassed a historic 50,000.

Already, the court-mandated supervision of the family by child protection workers had run its course. Chanel’s nine-month trial period was suddenly over, leaving her custody secure, just as new problems came along.

There was no telling what this summer might bring. Dasani could no sooner predict landing a spot on the Harlem team than she could foretell the abrupt changes that still lay ahead.

The markers of Dasani’s life — her first months in the care of Grandma Joanie, the day her family moved into their first real home, the loss of that home two years later, when they landed in the Auburn shelter — these all came in summertime.

It was only two months earlier that Dasani stood at the bus stop as her mother wept in the rain. Summer was fast approaching, a season that, in this family, always brings change.

“I thought it was a dream — make believe — like this wasn’t happening,” she says. “You know, like in movies, people pinch themselves like this ain’t real.”

But there is her beaming mother, Chanel; her father, Supreme; and all seven siblings. They are cheering and clapping as well.

Dasani blinks, looking out at the smiling faces. She cannot make sense of the serendipity that has brought her here to Harlem, on this sparkling July day, to make her debut as a member of an urban fitness group teamed up with Nike.

“She’s a giantess,” the man had announced to the audience. “She’s tomorrow’s success, I’m telling you right now.”

In an instant, she is midair, pulling and twisting acrobatically as the audience gasps at the might of this 12-year-old girl.

A mob of spectators presses in, trying to see the tiny girl. Rap stars circle. The cameras roll. The crowd chants her name. ■ “Da-Sa-Neee!” ■ Her heart is racing. She looks up at the sky and extends her fingers, but cannot reach high enough to grasp the metal bar. A powerful man hoists her up by the waist.

Chanel trails him, her chin high, her daughters’ hair freshly braided. It is a rare moment of belonging in a year of rootlessness.

As the sun sets, Dasani and her family step out for some air. A man brushes past them, walking along West 127th Street. His hooded sweatshirt is pulled low over his face, which is dusted by a salt-and-pepper beard. He moves with the purposeful air of a celebrity in hiding.

“I seen your videos,” Chanel says, stopping him in his tracks.

For years, Dasani’s family had been watching the DVDs of this former convict turned fitness guru who calls himself Giant. His team, Bartendaz, combines pull-up acrobatics on city playgrounds with a militaristic message of self-improvement, steering followers away from drugs and alcohol to “the bars of health.”

Giant looks Chanel up and down, noting the open beer she has sheathed in a brown paper bag.

“Bud don’t make you wiser,” he observes, flashing a smile that reveals a perfect row of teeth.

Chanel ignores the comment. She is already thinking through the possibilities presented by this accidental meeting. She steers Dasani to some empty pull-up bars at a nearby playground.

“Show him what ya got!” she calls out.

Giant, whose name is Hassan Yasin-Bradley, accepts the impromptu audition the way a famous film director takes the waiter’s latest screenplay. While Giant remains on the fringe of prime-time America, he has his share of acolytes in Harlem.

Dasani springs to the bars and begins to knock out an impressive set of pull-ups, her shoulders popping with the muscles of an action figure.

Giant is still chatting with Chanel when he looks over and pauses.

“Whoa,” he says.

Chanel senses that she may be on to something. She explains that Dasani has been doing pull-ups in Fort Greene Park for years. She can also dance, do gymnastics, run track. All she lacks is training — of any kind.

Now it is Giant’s mind that races through the possibilities. The girl is uncommonly strong. She has a telegenic smile. She’s spunky.

“She seems like just the kind of girl we could use on our team,” he says, grinning at Dasani, who grins back.

Giant quickly explains how his team works: It has a limited partnership with Nike that will hopefully lead to bigger things. In the meantime, the team earns modest pay in exchange for holding training clinics, and performing at concerts and other events.

At the very least, he concludes, Dasani merits a proper tryout.

“Meet me at the park next Saturday,” he says, leaving his number before disappearing.

Dasani lies awake that night.

It is the first time in her life she can see a path to something else. What exactly, she is not sure. She has not even had her tryout. But for a girl who has spent her life tempering expectations, she cannot stop herself from dreaming just a little.

“I’ma save all my money so we can get a house,” she tells her mother.

“Use your money for you,” Chanel says. “We’ll be O.K.”

“No,” Dasani insists. “I’ma save all my money.”

Money is especially tight. This might explain why, in Dasani’s words, Mommy goes “loco” during an inspection of the family’s room at Auburn. ■ There is a knock at the door. Chanel lets in the inspector, who promptly demands that she surrender the family’s forbidden microwave oven.

Chanel refuses. She cannot afford to buy a new one, nor can she fathom having to wait in line every night to reheat 10 dinner trays in one of the shelter’s two microwaves. The inspector leaves, and by the time two security officers with the Department of Homeless Services arrive to confiscate the microwave, Chanel has hidden it in a friend’s room.

As for the inspector, Chanel offers to “punch that bitch in the face.”

Dasani believes that her mother’s biggest problem is her mouth.

She reflects on this as her homeroom teacher, Faith Hester, delivers a lesson that week on personal responsibility.

“I don’t ever wanna hear, ‘Well, my mother told me to do this,’ unless you know that that’s the right thing,” Miss Hester tells the class.

The teacher has shimmied into an empty desk next to Dasani.

“I am telling you, as sure as I’m sitting here,” Miss Hester says, her arm resting across Dasani’s desk, “you’re gonna be held responsible for the choices you make.”

Hands shoot up in the air.

“Yes, Miss Dasani?”

Dasani recounts how her longtime rival, Sunita, began following her after school, and slapped her. “And so, my mom is a violent parent, so you can’t tell her anything about fights because then she gonna want to get a stick and tell you to knock the chick out.”

Miss Hester arches her brows.

“O.K.,” Miss Hester says. “Now, let me ask you: Do you think that was the right thing to do?”

The class erupts in chaos.

“O.K., O.K.!” Miss Hester yells. “I’ma tell you what I would have told my kid.”

They fall silent.

“Not everybody has something to lose,” Miss Hester says.

“You care about your life,” she continues. “There are people out there who are so hurt they don’t care about leaving here. They are looking for an opportunity to do something crazy and ridiculous. They have nothing to live for.”

Dasani ponders this.

“I am telling you to listen to your internal barometer,” Miss Hester says. “Think about your next move before you make your next move.”

Dasani is still in bed the next morning when her mother rises from a fitful sleep and heads to the corner store with her sister Avianna. All around, men are leaving the projects to report to early work shifts. Chanel stands in the cold, watching them. “Your father should be doing that,” she says.

Just that week she had stopped a flag waver at a construction site. It seemed like a job that Chanel could perform beautifully. The woman told her about an organization that helps people with G.E.D.’s find work.

For Chanel, words like “G.E.D.” end a conversation. It has been 20 years since she sat in a high school classroom. She can feel like a foreigner in her own country, unable to speak the language of bank accounts and loan applications. When filling out medical forms, she stops at the box requiring a work number, frozen by its blankness.

“I want my kids to be able to come see me at my job, pick up my paycheck,” she says that afternoon, standing with Dasani outside Au Bon Pain, where the day’s pastries will soon sell at a discount. “Just be reliant on my money, you know what I’m sayin’?”

Dasani stares at her mother anxiously.

“I’m tired of my kids seeing me dull,” Chanel says. “It’s my time to shine.”

“I don’t see you dull,” Dasani says quietly. “I see you shine.”

Dasani spends the week before her tryout for Bartendaz in focused preparation, training on the fitness bars next to the basketball court in Fort Greene Park in Brooklyn. At night, she replays the team’s DVDs over and over, studying the members closely.

At school, she tells no one.

This new dream is carried on practical terms. It is less about helping herself than about making her parents whole. In the meantime, Dasani worries about the most immediate challenge, which is to get to Harlem on time. Punctuality is a miracle in her family.

On Saturday morning, there is no sign of Dasani as the Bartendaz start to warm up at the playground at 144th Street and Lenox Avenue.

Soon they are causing a commotion that slows the traffic. One after another, they fly onto the bars, whipping through moves that seem to defy gravity. Some of them wear black T-shirts with the logo of a man bending a bar, his brain lit by a bulb.

“Salute that mind!” Giant calls out to his followers.

There is Cinderblock, Honey Bee, Sky, Earth, Water, Blaq Ninja, Salubrious and Mel Matrix. Giant’s second in command is Dr. Good Body, a self-described athletic alchemist (“the library is my alma mater”) who transforms the “base metal” of a person’s character into “gold.”

Giant orbits around his team, issuing commands in a lyrical code that is impenetrable to outsiders. He is especially fond of abbreviations. A favorite is “C.A.P.” — Character, Attitude and Personality. His nickname, Giant, stands for Growing Is a Noble Thing.

It is a bold name for a man who stands just 5-foot-7. Born Warren Hassan Bradley, he grew up in the Baruch projects on the Lower East Side, where in his teens he became known as a D.J. and street fighter skilled at hiding razors in his mouth and spitting them out in combat. He started selling drugs, and was sent to prison in 1989 on two felony drug charges.

Like Dasani’s father, Giant left prison transformed. He had earned a high school equivalency diploma and devoted himself to Islam. (He looks askance at the teachings of the Five Percent.) He also found a way to capitalize on the pull-up bar routines that he taught himself in prison yards. By the time he started Bartendaz in 2003, he was already drawing crowds to Harlem’s playgrounds.

Dasani finally arrives, her mother and two siblings in tow, as the team’s practice winds down. Dressed in bright-pink shorts and matching flip-flops, she is a dwarf among titans.

“What’s your name again?” Giant says.

“Dasani.”

“Dasani with a D?”

“Like the water,” Chanel says.

He turns to the group.

“Everyone say, ‘Peace, Queen.’”

“Peace, Queen!” they shout.

The tryout begins with a set of pull-ups, demonstrated by Blaq Ninja and Sky. Dasani coasts through the exercise.

“Damn!” a team member says as the others whistle. Giant remains cool to the newcomer, telling Dasani “stay there, breathe” as she pedals her feet in the air while holding her head level with the bar.

Her next test comes on the parallel bars, where she knocks out a set of dips in good form, and then pedals again as Giant counts aloud, shaking his head incredulously. Next, they hit the floor for push-ups.

“Do some diamonds!” Chanel calls out. Dasani connects her hands in the shape of a diamond as she dives into a set of flawless push-ups.

Then she goes for broke, clapping her hands behind her back, mid-push-up. Honey Bee captures the image on the team’s iPad before Dasani comes crashing to the ground, promptly dusting herself off.

“Look at this! Look at this!” Giant says, running over to show Dasani the iPad photo. “You tellin’ me I can’t sell this poster for $100?”

He turns to Chanel: “She’s in.”

A young boy sidles up. The team has drawn spectators who live as far away as Norway and Japan. This one is a local.

“Excuse me,” he says to Dasani. “Can you do a pull-up again?”

She nods gamely as he calls out to his friends: “Yo! Come here! She about to do it!”

Giant smiles.

“Wait till they see you in three weeks,” he says.

The family is ecstatic.

Supreme runs to the corner store for a dozen roses. He hands them to Chanel.

“Dag, I love it here,” he says, looking at her tenderly. “We should come back to Harlem.”

Chanel soon finds reason to be suspicious of Giant. He is charming, she thinks, but confusing on details like payment and a promised contract. Giant, too, can spot a hustler, and he seems wary of Chanel. ■ On the day of the tryout, he treats her children to lunch at a local bodega, joined by Malcolm X’s grandson Malik, a friend of the team. Malik congratulates Dasani, handing her a bottle of peach-flavored Snapple. She carries the bottle with both hands, later writing “Malcolm X grandson” on the label before stashing it in her dresser at Auburn.

The next day, when Dasani’s siblings tag along to practice again, Giant senses that Chanel expects him to repeat the invitation.

He skips the meal, but reassures Chanel that her daughter, like his other team members, will be compensated for events. The first one is a training clinic this Thursday. All Chanel needs to do is bring Dasani. The rest is Dasani’s job.

“That’s why we got the word ‘responsibility,’” Giant tells Dasani in front of Chanel. “Response” — he holds up his right hand — “Ability” — then his left hand. “So respond to what? Your ability. Not your mom’s ability.”

On Thursday afternoon, Dasani asks if her mother has heard from Giant. Chanel is tired after a long day and cannot imagine taking Dasani all the way to Harlem.

“He never called,” Chanel tells Dasani.

Up in Harlem, Giant had been calling repeatedly. He checks his phone, looking for a response. He shakes his head.

Dasani goes to sleep feeling crushed.

She wakes at 5 a.m. for the long-awaited school trip to Washington. Still feeling glum, she boards the bus on an empty stomach, sitting alone with a thin blue blanket laid carefully across her legs. Five hours later, as they approach the Capitol, Dasani presses her face to the window.

It looks different here. People walk slower. There is space everywhere — trees, monuments, water. She can see off into the distance, her view unobstructed by skyscrapers.

She is paying special attention, trying to record what she sees so she can describe it later to her sister Nijai.

Remember every single detail, Nijai had implored. It is not just that her blindness prevents her from seeing it herself. It is that Washington represents Nijai’s roots, the city where she was born and last saw her mother alive.

Every detail.

After a tour of the memorials, the bus stops near the White House. Dasani runs to the tall, wrought-iron gate and looks between the bars. On the sidewalk, a group of protesters wearing orange suits and black hoods are chanting foreign-sounding names.

“Obama, close Guantánamo!” they yell.

Dasani has never heard of Guantánamo. But she knows what a jail uniform looks like from visiting her Uncle Carnell. These people, she concludes, are supposed to be prisoners, and they want President Obama to close their jail. She shakes her head.

“I don’t know why they protesting in front of Obama’s house like he gonna be in here,” she says.

There is hardly a trace of the child who had once scoured Gracie Mansion for a glimpse of the mayor.

A week has passed with no word from Giant. Dasani keeps doing her pull-ups. Tucked in the top drawer of her dresser is the empty Snapple bottle given to her by Malcolm X’s grandson. ■ “It’s all right,” Dasani tells her mother. “I didn’t get attached.”

Detachment is as much a rite of Dasani’s summers as sunbaked afternoons in the park. She bids farewell to Miss Hester and the principal, Paula Holmes, bracing herself for a 10-week absence from the Susan S. McKinney Secondary School of the Arts.

Summers also bring more regular visits to Grandma Sherry’s, where the children can ride up and down Lincoln Avenue on rusted bikes. But this year, Sherry has bad news. The bank is coming for her house. In another month, a court marshal will see her out the door if she is not gone.

Sherry has two bad choices: She can enter the shelter system or she can leave her children and grandchildren behind in New York and move in with her sister in Pittsburgh. If Sherry leaves, Chanel will have lost her only support, the woman who partly raised her.

Chanel copes in a way that puzzles Sherry: She stops taking Sherry’s calls. It is Chanel’s way of detaching, of leaving a relationship before it leaves her. Sherry finally decides to go to Pittsburgh. When she does get the children on the phone, she tells them that she is not sure when she is leaving, but that “the Lord will take care of you.”

In the midst of this, Dasani finds herself thinking about Bartendaz. A month after her tryout, she resolves to give it another chance: She will report to practice by herself, as if nothing has changed. But as she announces her departure one morning, Supreme stops her at the door.

“Not before this place is straightened up,” he says. By the time Dasani finishes, practice is over.

The next morning, she gets up feeling defiant. She looks at Supreme, who is still asleep. How you gonna take my destiny away from me? she thinks. Dasani turns to her mother, and Chanel waves at her to leave before he wakes.

Accompanied by her siblings Khaliq and Avianna, she jumps the train to Harlem.

“Long time no see,” Giant says by way of a greeting. He gives Dasani a stern lecture: “If you know you’re not gonna be consistent, then I need to know so I can invest in someone else.”

Dasani is confused. Her parents say that he never called. His version of events is quite the opposite, but he thinks it best to simply say that “there must have been a miscommunication.”

Dasani does not know what to believe, but she begins training with Giant every weekend, accompanied by her twin in all things, Avianna.

They are in Harlem on the day a moving truck pulls up to Sherry’s house. Alerted by phone, Chanel arrives moments before Sherry’s departure.

“I’ma hide in the truck,” 8-year-old Maya says.

Chanel walks through the house she has known since she was born. She pauses at the bathroom’s worn wooden door, which reminds her of her father.

He is there at that door, some flicker of a memory. Those are the things one loses with a house, not the shelter itself but the irretrievable belonging it brings.

On the stoop, Sherry and Chanel hold each other for a long time.

Dasani does not get to say goodbye.

The sadness of Sherry’s departure is eclipsed a week later when Dasani makes her big Bartendaz debut. Her routine is captured on video for the opening sequence of Giant’s forthcoming DVD, and Dasani receives her first earnings: $70.

She is too excited to think twice when Supreme asks if he can borrow some of it. He buys pizza for the children and keeps the rest. Dasani is distracted by the day’s other gifts — the cheering crowd, the chance to pose with the rappers Jadakiss and Styles P.

She is still floating two days later, when Giant summons her to a basketball clinic for boys. He wants her to “mentor” them. It seems like an odd request for a girl who was recently suspended from school. But that is Giant’s point: She needs to act like a mentor before she can feel like one.

She soon takes to the task, guiding boys several inches taller as they struggle into feeble pull-ups. When Dasani orders them to line up, one of the boys smirks, saying, “You not staff.”

“Oh yes I am,” Dasani shoots back.

She is bonding with her team — most of all with Sky, a nursing student, and Earth, who just got her bachelor’s degree in psychology at Queens College.

“I’ma take all of Sky’s moves,” Dasani says jauntily as she hits the low bars. They laugh and laugh, never ceasing to delight in their youngest member. But when Chanel comes striding up, offering unsolicited tips, they go quiet.

Later that afternoon, Dasani tells Giant about her loan to Supreme. Long after she leaves practice, he is still livid. Can this even work, he wonders. “You’re fixing a child to send back to broken parents.”

Summer’s end marks the third anniversary of Dasani’s arrival at Auburn, on Aug. 26, 2010. ■ Three years — a quarter of her life — most of it spent in one room. She has gotten so used to the smallness of it that she can scarcely recall how to live with more space.

To Dasani, sometimes it seems like only tragedy brings change.

The next morning, on Aug. 27, she wakes to a high-pitched scream. It is her neighbor in Room 445, a single mother named Aisha. Her 3-month-old daughter, Casshanae, has turned blue.

“My baby’s not breathing!” she wails.

A petite 27-year-old from Pennsylvania, Aisha had come to Auburn in early May, seven months pregnant with Casshanae. She was born premature with respiratory distress syndrome and developed feeding problems, all of which was noted in the records that Auburn received.

The infant’s problems were serious enough that a hospital social worker asked the Department of Homeless Services to transfer the baby, Aisha and her 1-year-old son to another shelter equipped to handle medical needs.

The agency declined to do so, even after Aisha filed a complaint that a male resident had sexually assaulted her in her room at Auburn on June 18.

Nor did the shelter’s staff members heed Aisha’s repeated complaints when they gave her a damaged metal crib for the infant, with a loosefitting sheet and a mattress permanently stuck in the lowest position.

But now she is screaming, and everyone hears her.

A security guard calls 911. None of the staff members try to resuscitate the baby, even though they are certified in CPR. Aisha fumbles to breathe air into her baby’s lungs as paramedics rush into the lobby.

They race to Brooklyn Hospital Center, where a doctor pronounces Casshanae dead at 8:10 a.m.

Later that morning, Aisha returns to the fourth floor to pack her things. Her screams rattle the shelter again.

As she leaves, Dasani lingers by the door. She hears a security guard telling a superior that Aisha left the children alone the previous night. The official asks the guard to file a report. Dasani shudders and closes the door. That will never happen to Baby Lele, she tells herself.

The next day, the Administration for Children’s Services takes custody of Aisha’s son pending the results of an investigation into the baby’s death. Soon after, Dasani sees inspectors walking through the shelter as new cribs are delivered to residents and crib-safety posters are slipped under doors.

Aisha is summoned back to Auburn by investigators from the medical examiner’s office. At their request, she re-enacts the morning of her baby’s death, when she says she found Casshanae lifeless in the crib. They take pictures of the crib, its sheet still crumpled. An autopsy was unable to determine the cause of death.

Dasani tries not to think about the dead baby. ■ Her room is sweltering. The children want nothing more than to get out and cool off. They put on their bathing suits. They have gone swimming only once this summer.

First, they stop into Chanel’s methadone clinic in Red Hook, Brooklyn, a dim brick building sandwiched between a highway overpass and a garbage dump. Chanel waves at Dasani to come inside.

She has been bragging to the staff about Giant, who continues to work with Dasani on the condition that she is paid in kind, not cash. “No one can take a pair of sneakers,” he reasons. “He just stingy,” Chanel says. But she has gone along with it, proud as a stage mother.

“So look out for Dasani, man,” Chanel tells a woman behind the desk. “She gonna be out soon.”

“I believe I am already out,” Dasani says.