"Change your costumes," the kids are told, and now, imagining themselves on the big stage of the Iron Gate Theater, where their show will be performed, they squeal toward a stash of grandmotherly pearls and faux tambourines. A new beat starts. The kids dance again. They dance and they laugh and they sing.
Down the hall, in another room, the fourth graders of Benjamin B. Comegys are throwing down their own rehearsal - the boys going first, the girls stepping up and keeping pace. They stop for a moment to videotape a thank-you to their teacher, and then they're counting themselves in to a new beat. They haul some improv moves out of their imaginations for my long-snouted camera. They run around to my side of things to be sure that my takes are newspaper-worthy.
"Mouth is open on that one," one boy tells me. "Use the second picture instead."
"You having fun?" I ask.
"Heck, yeah," he says, and then he returns to the line, where he's needed.
A self-sustaining organization run by Penn undergrads, CityStep, in the words of its website, "introduces public school youth to the performing arts as an outlet for creative self-expression, a tool for building self-esteem, and a means to mutual understanding." It got its start at Harvard in 1983, when an undergrad named Sabrina Peck looked for ways to bring dance to Cambridge classrooms - and succeeded.
The program was "colonized" at Penn in 2004, where it now includes more than three dozen Penn students who travel to five West Philadelphia schools - Powel (fourth grade), Comegys (fourth), KIPP West Philadelphia (eighth), Samuel B. Huey (fifth), and Andrew Jackson (fourth through sixth) - twice each week throughout the school year to teach eight-counts, improv, and, on some days, Chubby Checker.
Leah Apple, the program's co-executive director, credits CityStep with giving her a way to reach beyond insulated borders and learn from those living lives unlike her own. She's a Penn senior now, a new Fulbright grant winner, an amateur hip-hopper fluent in conversational Mandarin who is very serious about the silly. She's also one of my former students.
Leah joined CityStep as a freshman. She wrote about it in my class as a sophomore. And now, alongside Philine Cheng, she has helped select and lead the undergrads on the team while at the same time working with the educators, administrators, parents, and children who benefit from this unusual breed of outreach.
Helping run CityStep is a job, Leah says, that tests you, foils you, keeps you up way past the gloaming hour, and, insistently, matters.
"When you dance," Leah explains, "you have to battle your own self-consciousness. When you teach children to dance, you have to exaggerate your own willingness to be free; you have to be willing to demonstrate the power of that freedom - to give them that power."
And it is, so clearly, about power. The children of West Philadelphia who dance with CityStep are living at a time of dwindling arts funding. They're living in an era when it is essential to open doors to Penn's Ivy campus and to give children a good and hopeful look around. Dance is always about expanding possibilities. CityStep tugs and nudges the horizons.
"It's inspiring to see these kids fall in love with the performing arts," says Philine, whom Leah credits with keeping the company's many moving parts well-greased. "It's even better to see their confidence growing."
CityStep has, Leah tells me, broken down barriers, changed ideas - in the minds of Penn undergrads and in the minds of the children and their parents - about what healthy collaboration can look like. It has also planted seeds about self-esteem. It has shown children who don't have enough that the world is big, and that many people care.
"The kids show up to dance, but they start thinking about college," Leah says. "They put on a show and they make their parents proud. They look at the guys in our organization and see new kinds of male role models. They show us their moves, and we show them Chubby Checker."
And then, once each year, it all comes together on a shared stage on the Penn campus. This year the show is called "CityStep Presents: Intramural," a reference to the inspiration the choreographers have taken from such Philadelphia murals as "Bridging the Gap," which tells the story of West African immigrants, and "South Philadelphia Musicians."
It's a little scary, the young dancers tell me, as rehearsals end. A little scary, but clearly a whole lot of fun. It's a whole lot of whole, as a matter of fact, and that's what matters most. Bridges forged and bridges crossed, and nobody standing in the margins.
"CityStep Presents: Intramural" performs Sunday at 3 p.m. at the Iron Gate Theater, 3700 Chestnut St. For more information, visit http://citysteppenn.org/.
Beth Kephart is the author of "Dr. Radway's Sarsaparilla Resolvent," about 1871 Philadelphia, which is being released Tuesday. She teaches memoir at Penn and blogs daily at www.beth-kephart.blogspot.com.