Before dawn on Inauguration Day, a military vehicle will leave the Pentagon. Its mission: escort a busload of California schoolgirls deep into the nation’s capital.

Who are these special young ladies? They’re members of the San Francisco Girls Chorus, who together with the San Francisco Boys Chorus, are the only charitable ensembles performing during the inauguration ceremony. The choruses, invited in November, will jointly perform a 20-minute medley of patriotic songs.

“We have friends in high places,” says Melanie Smith, executive director of the girls chorus, of their opportunity to sing-in the new president. (The chief “friend” would be Sen. Dianne Feinstein, Democrat of California, who chaired the committee arranging the ceremonies.)

The Girls Chorus, whose members range in age from 9 to 17, has raised 70 percent of the $70,000 the trip will cost. The boys ensemble, meanwhile, has already raised the around $100,000 it needs to send 43 boys aged 9 to 14 to Washington. (The boys—largely younger than their female counterparts because of the whole voice-changing thing—require additional chaperones, and thus additional money.)

Ms. Smith’s singers will be hosted at a boarding school in Middleburg, Va., about an hour west of Washington. While happy to have a place to stay in a metropolitan area inundated with visitors, the logistics will give the girls a long day.

“I think we have to leave the boarding school by 3:30 in the morning to meet our escort at the Pentagon,” Ms. Smith says.

The boys will be bunking down at a Marine Corps barracks in the Washington suburb of Arlington, Va.

“The boys are so excited,” says Elaine Robertson, program manager at the boys chorus.

But are the Californians all that excited about performing in Washington’s chilly wintry weather?

“Oh yeah,” Ms Robertson says. “We got long underwear donated for all the boys.”