A group of 10- and 11-year-olds giggle as professional cellist Frederic Rosselet flexes his wrist as if he's made of rubber. "Really flexible in your wrist," he tells the students. "It's your arm basically that does the work."

The cello students at Downer Elementary School in San Pablo, Calif., drag their bows across their cello's strings, following Rosselet's wrist-shaking lead.

Screeeech. It needs work.

"Guys, wanna try that again? 'Forte' means?"

"Loud!" the students reply.

"OK, let's look at bar 22. Three and four and ... " The screeches at the start of class slowly start to sound like something resembling Beethoven's Sixth Symphony, or at least the section of it these students are working on.

"That's already a little better," Rosselet says with a faint smile. "Good."

Scores of orchestras across America do some kind of music-education outreach.

But few of them are embedded in the life of a school three days a week. That's what the Sound Minds program is doing. It was created in partnership with the California Symphony, a professional orchestra based in Walnut Creek, Calif., that plays in the Bay Area.

The organization has musically adopted Downer Elementary, located in a predominantly lower-income city in the northeast part of the San Francisco Bay.

The symphony pays for professional musician-educators to teach a focused curriculum throughout the year, from music fundamentals to individual and group cello and violin.

So far it has paid off: Participants are testing higher in math and reading than students who aren't in the program. But Sound Minds, its creators say, also promotes music's intrinsic power to uplift, inspire and challenge.

After all, schools in lower-income areas often see fewer music and arts programs than their wealthier counterparts.

"Our families are working-class, and sometimes the invisible class," says Downer Elementary Principal Marco Gonzales. "They're finding work where they can find work. They're cleaning houses. They're digging ditches."

The school serves mainly struggling Latino families, many of them immigrants from Mexico. More than 95 percent of its students receive free and reduced-price lunch.

"Some of our families are undocumented, that's not something we look into," says Gonzales (who, I found out after reporting this story, is the brother of my NPR colleague and veteran correspondent, Richard Gonzales.)

"And so a lot of our families are on the fringe of society — and in the shadows," the principal adds. "They've left their comfort zone to make a better life for their kids."

Music is now a pillar of his strategy to help forge that better life — out of the shadows. The Sound Minds program is free for any student who wants in. It's modeled on El Sistema, Venezuela's pioneering music program that reaches out to impoverished kids.

Classical music organizations across the U.S. are struggling to attract younger audiences, stay afloat and stay relevant. So is it a tough sell, reaching elementary students — a demographic that loves pop music and TV shows like The Voice and American Idol?

Ten-year-old Jocelyn Castaneda, who studies the cello, says it isn't for her. "It just gets me happy," she says. "And I'd rather be doing something that I love to do, instead of just watching TV which I can watch anytime."

Principal Gonzales agrees. "We bring something to the kids' lives that they may not even dreamed about, but is a common reality in other communities where you do music or you do gymnastics or you do sports after school and your parents pay for it," he explains. "Here, we're able to provide it for free and our parents have been enthusiastic. They're proud of their children."

Children such as 11-year-old Carlos Garcia. He wears glasses and a slightly mischievous smile. He's a small guy. His kid-sized cello seems almost as big as he is. He has stuck with the instrument for more than four years.

After class, I ask him what he likes about the cello.

"It's like a shark's following you, you know."

Wait, it's like a shark is following you? Explain that.

"In the movie, like, when a shark is following you and wants to eat you and they play, like, a song."

Ahh, the famous John Williams score from Jaws. Big cello part. Got it.

"You could go to Hollywood, play, and be rich, yeah," Carlos says confidently.

Hollywood cellist. I like it, I tell Carlos.

"I kinda like it, yeah," he says.

Amy Haltom joined Sound Minds precisely to teach less-affluent kids who might not otherwise be exposed to the arts and music.

"It's all well and good to perform Bach cantatas to appreciative audiences in the Bay Area," she says. "But I reached this point in my career where I asked 'what is this all for?"

Haltom moved from San Francisco to Richmond, right next to San Pablo, to be closer to the life of the school community. "This is my purpose!" she says. "For me it's been tremendously life-changing personally and professionally."

Before students in the program can take up the cello or violin, they have to take an introduction to music fundamentals, which includes the basics of sight reading, beats and rhythm.

Advocates for music education often say that studying music boosts overall learning. A few studies have shown a link between music training and improved reading skills.

The California Symphony says its own crunching of Downer's standardized test data show that students who've been in Sound Minds for one year are achieving far above their peers.

"In third grade, they are testing at math proficiency rates, meaning testing at grade level or higher, at quadruple the rate compared to their peers who are not enrolled in the program," says Aubrey Bergauer, the symphony's executive director.

And in reading scores, they're seeing similar results. "Most of these kids are learning English as a second language, and to see these kinds of results off of a primarily music education program is phenomenal," Bergauer says.

But this is just one elementary school. The big question is whether this kind of program can be replicated on a wider scale.

That would mostly come down to money. The symphony spends some $80,000 a year on Sound Minds, and the school another $20,000, not including facilities.

The rest of the schools in the West Contra Costa Unified District — and many schools around the country — aren't so lucky. The district spends an average of just $5,000 a year per school on music education.

The symphony wants to spread the program to other area schools. But that remains mostly a dream.

"One lesson we've learned is don't go too big, too fast," Bergauer says. "We learned that we can make a bigger difference if we invest here at Donner Elementary first, grow this program, adding new students to it every year while continuing with the original class."

Christopher Woodside, with National Association for Music Education, is grateful for any and all interest in building quality music programs in schools. But, he argues, there has to be a much bigger effort nationally to help close the opportunity gap between rich and poor districts.

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