COEUR d'ALENE - Crowds were waiting impatiently along Sherman Avenue on Friday evening.

Police kept watch where they had cordoned off the streets. Kids craned their necks, adults prepared their cameras.

In the distance, an army of folks in white and blue approached, rousing exclamations from onlookers.

An important clue: This was not a parade.

A few folks in the crowd hadn't heard.

Murmurs of, "What's going on?" rustled through the throng as the individuals took positions on either side of Fifth Street.

They were of all ages - grandmothers, 20-somethings, some tots. Even a few men.

Someone in the crowd supplied an explanation: "Flash mob."

Suddenly speakers along the curb exploded with Katy Perry's "Firework."

The group burst into action. Following leaders at the head of the pack, they swayed, stepped, sashayed.

There was some hip hop, some fancy arm work, some twists and turns.

Through it all, the bodies were cleanly in sync, pivoting and stepping like a giddy army.

But this was not your typical flash mob.

Aside from being not quite as spontaneous as other incidents of random public choreography, this coordinated dance had been organized as a fundraiser for both the Kootenai County Boys and Girls Club and the MEB Foundation.

Participants had to contribute at least $20, and learned the steps from a video posted online.

It was definitely a success, deemed co-organizer Alex Endo, especially with only a couple rehearsals.

The most recent had been earlier on Friday.

"People who participated didn't realize it would be tonight, until they got there," he said.

Endo, associated with MEB, supported a flash mob as an unorthodox fundraising idea, though he hasn't counted how much has been raised yet.

People were thrilled to get involved, he said, evidenced in their practicing.

"Everyone had a great time," Endo said, adding that more than 140 participated. "The city was totally shocked."

Applause echoed in the street when the performers finished on Friday.

Bob Sicaro met up with his family, who had all participated.

That included his wife, Cathy, their daughter, Lisa Finan, their grand daughter, Cheyenne Finan, and friend Carrie Braasch.

"Everybody except me," Bob said. "I can't dance."

The Coeur d'Alene family practiced together at home, Lisa said.

It was a bonding experience, she said, adding that her 9-year-old daughter picked it up with ease.

"She hung in there," Lisa said.

The whole group has wanted to be in a flash mob for awhile, Cathy added.

"Just being out in public, dancing in the street, we thought it would be fun," she said. "It was a blast. The people who we worked with were really fun. We would do it again in a heartbeat."

Twelve-year-old Emily Hunter rushed to meet her father, Craig, who had watched her perform a few feet away.

"She's been practicing at home every day," Craig said.

The Lake City girl decided to join up as soon as she saw a flier advertising the event, she said.

"I've always wanted to do a flash mob. It's my No. 1 dream ever," she said with a grin. "Just something about it I just love. Everybody gets together as a community and comes out."

Despite Emily's background of dance lessons, she said, stepping on the streets is a whole different beast.

"It was kinda weird when everybody started crowding around and watching," she said.

Sheri Martin, sitting with friends at the Moose Lounge patio, said she was thrilled by the surprise of the performance.

"It was unexpected," she said. "We were just sitting here, having drinks at the Moose."

Martin has only seen a flash mob before on the show "Modern Family," she added.

"They did a great job. It was coordinated very well," she said with a smile.

Erica Danforth, eating at the Iron Horse patio with her father, said she was generally indifferent to flash mobs.

"It was just something to watch," the Hayden woman said.

But the coordination was impressive, she said.

Would she ever do a flash mob?

"No," she said with a laugh. "I don't think I could do the moves. They were really going to town. I don't think dance moves are really my thing."