The adult performers included the song’s originators, Robbin Thompson and Steve Bassett, backed by Susan Greenbaum, Samson Trinh and the Upper East Side Big Band. And there was this curly-headed, barefoot kid named Jason Mraz, whom, judging from the screams in the audience, a few people knew. The SPARC alum caused mass swooning when at the front of the stage he announced, “To get me to come here, all SPARC needed to say was, ‘Please.’ ”

And to be fair, there were dozens of barefoot kids up there because they were using them to paint. Their effort was hoisted up before the audience toward the end of the show, like the Elevation of the Host accompanied to wall-reverberating applause, too.

SPARC’s educational director, Erin Thomas-Foley, had a dream when pregnant about an en masse celebration of youth and art. She didn’t have any idea about how to pull something like that off, and didn’t even mention it for a long time, until in a meeting with SPARC’s director Ryan Ripperton. The concept fit into the statewide arts initiative, Minds Wide Open 2012, this year dedicated to young people in the arts. Live Art, which brought in children of different abilities and put them together in a public showcase following a 20-week educational program, broke new ground. There’s nothing quite like what was accomplished last night.

I’ve seen plenty of shows at the Carpenter, big and small, but this was different: part community showcase, part recital and all heart, with production values worthy of Broadway. As one actor who’d been watching the Queen’s Diamond Jubilee events during the past few days commented, “This was just as good as anything they did.”

One left with a sense of uplift and unifying spirit. The first headline you hear or read may crash all that, but for those who watched, but most specifically those who participated, it’s not likely to be a quickly fading memory. Last evening’s show, beyond being a tremendous success (even based on sheer logistics alone), was something to build on.

The presentation of scenes by mimes and musicians in between the big production numbers proved to be a deft touch. They started the spectacular with a young man in a three-cornered hat carrying a wind-up gramophone in front of the curtain. He cranked it up, and the show rocked to life.

And there were many tear-streaked faces at the end.

At the end of the late 19th and early 20th centuries, Richmond's streets hosted downtown trade shows and fairs and even Halloween parties that closed Broad Street (not to mention the Tobacco Bowl Parade). This past weekend's events were great signs that our city, after many years, is finally coming to understand one important thing: If we're all here, we may as well make the best of it and have a good time when we can, supporting good causes in the process.