With the rhythm of African drums pounding, the boys in lacy white tunics and embroidered vests dipped their knees as they snaked through the suburban Maryland ballroom last Saturday night.

It wasn’t a wedding, though it looked festive.

Tween-age tourists staying at the hotel and chasing each other through the lobby in their pajamas stopped to look in: “What is going on?” the one with braces and a bristle-cut asked.

“Maybe a dance or something?” the one in skull pants answered.

Past the hotel chairs, between the white tablecloths, the boys in Nigerian garb danced, showered in wads of cash.

Then the girls came, shimmying in purple satin, arm bangles rattling, the bells strapped to their legs ringing with each step, giving music to the sound of fluttering $20 bills.

They were dancing for a new hospital facility, for textbooks and for medical supplies, for a place in Nigeria many of them have never even visited. By the end of the night, all those bills added up to about $11,000.

It’s a whole level of micro-aid that isn’t necessarily on the radar of most Americans.

That account executive in the cubicle next to us? She helped build a hospital wing back home.

The bartender downtown? He built an entire school in his home village.

The cabbie driving you to your important meeting? He supplied books for a whole town.

Forget wire transfers. Goodbye, envelopes of cash sent with someone going back home and the hopes the money would actually make it. And no, thanks, giant international aid organizations.

The gala in a Beltsville Sheraton looked more like a high school prom than nation building. But that’s what it was, a kind of immigrant fundraising that is hands-on and completely in control.

“With a big organization, you can’t be specific about where the money goes; you have no control, but you just hope it helps,” said Atai Nyambi, president of the charity that put on this affair, Nka Ikem Esit, loosely translated as Like-Minded People in the language of Efik.

“But for us, we know the people on the ground. I personally spoke with the chairman of the hospital we are helping. We set up a task force; we know exactly what their needs are and what it costs to make it happen,” said Nyambi, who by day works as a resource coordinator in Prince George’s County, in an office, with a desk and such.

On Saturday night, Nyambi looked like an African queen, in a swirling, royal blue headpiece and gown, surrounded by the children in native costume. She’s been in the United States since 1975.

We laughed when I told her about the ways I remember my immigrant parents trying to send help back to their home country in the 1970s. It didn’t involve dancing and dinner.

They stuck the cash between two pictures glued together, after a costly lesson when government screeners at the Czechoslovakian post office somehow managed to lose all the other envelopes that had cash they could detect with the help of a desk lamp.

“It was always so risky to send cash back home for us, too,” Nyambi said.

So in 1993, she and a few others from her native Calabar, a port city of 180,000 people, formed their organization, based in Maryland. At first, they created a scholarship and collected books to send back home. But over the years, the needs of their community became more clear.

They learned that medical supplies were in dire need, stuff like tubing and gauze that in the U.S. might linger in a doctor’s storage facility or a dentist’s closet because newer stuff just came in.

So they got those doctors and those dentists to donate the supplies and raised money to send it all back home to Nigeria.

Then someone from Calabar sent a picture of the waiting room in the maternity and children’s section of a teaching hospital. It was nothing but a dirt floor and the walls. The fundraisers transformed it into a comfortable waiting room, complete with a microwave and refrigerator.

“For me, I like helping schools back home. I know what the children need and what they don’t have,” said Kenny Ogundimu, an accountant for Fannie Mae who now lives in Clarksburg, after emigrating from Nigeria in 1980.

The United States is the world’s biggest exporter of remittances — cash sent by migrants to their home countries. And despite the ragged economy, most home countries are still benefitting from the largesse of their emigrants.

Nigeria is the biggest recipient of remittances in all of Africa, according to a report to be released Thursday by the World Bank. And the money transfers from relatives and fundraisers such as the one in Beltsville are outpacing foreign direct investment and official development assistance.

And by directly controlling where that money goes — schools, hospitals and so forth — the accountants and cabdrivers and doctors celebrating in a Sheraton ballroom are making social change on a global scale.

So that’s your answer, tourist boys. What were those kids in bells and beads and tunics doing in the hotel that night? Changing the world, one dance at a time.