If you’ve been to the Austin City Limits Music Festival in the past decade or so and arrived early, you’ve probably heard the Barton Hills Choir. It’s a great way to start an ACL Fest day: Before the big names and buzz bands take over the main stages across Zilker Park, a few dozen fifth and sixth graders from Barton Hills Elementary School set the tone for the weekend in the Austin Kiddie Limits area, raising their voices and hands in celebration of the music everyone’s there to hear.

Last year, they brought side two of “Abbey Road” to life, many hours before Paul McCartney himself led his band through the classic Beatles medley on the fest’s biggest stage. The previous year, Austin guitar great Charlie Sexton led the kids through a tribute to the late David Bowie. And then there was 2014, when indie band Belle & Sebastian was so enamored with the choir that leader Stuart Murdoch not only took part in their performance, he also brought them onstage to sing with his own band later in the day.

The choir’s days in the sun aren’t limited to ACL Fest, though. On Sept. 13, they’ll celebrate the release of a new CD, “Rock the Classics Vol. 1,” with a performance at downtown club 3Ten. The disc features that “Abbey Road” suite and an Elvis Presley medley they worked up a couple of years ago for a South by Southwest premiere of an Elvis documentary film, plus favorites from the likes of Joni Mitchell, Neil Diamond, Carole King, Talking Heads and the Grateful Dead.

WATCH: Barton Hills Choir sings the Grateful dead's "Touch of Grey"

It all began two decades ago, when Barton Hills Choir director Gavin Tabone stumbled upon a career direction that, in hindsight, seems to have been his destiny. Raised in Cincinnati, Tabone moved to Nashville for college in the 1990s and got a musical arts degree at Vanderbilt University. Drawn to Austin by its lively music scene, he hoped to play keyboards and write songs for a living.

“I knew that I enjoyed teaching, but I didn't think I wanted it to be a profession,” he says. “It was natural for me, but I wanted to be a full-time musician. I wanted to compose. And when we moved here, that was my plan.” He soon joined King Soul, a lively local outfit led by Tom Clifford that’s now based in Clifford’s hometown of Washington, D.C.

But fate intervened. To pay the bills, Tabone got a job as an outreach supervisor with the city’s Parks & Recreation department. “I’d set up in a park and play all these games, kickball or whatever, with the neighborhood kids," he says. "My goal was to recruit them into the neighborhood rec center.”

This was in the Dove Springs neighborhood, near Palm Elementary School in Southeast Austin. Through the children, he got to know some of the teachers at Palm. “I found out that the music teacher was moving, and that's when the principal asked me if I wanted to teach,” Tabone says. “I didn't have a teaching certificate, so they put me on an emergency certification plan.”

Tabone first worked as a teaching assistant while taking night and weekend classes with an Austin Independent School District program for aspiring teachers whose college degree wasn’t in education. Eventually he took over as the school’s music teacher.

“That first year at Palm, my classroom environment was good, but I didn't know what I was doing. I learned kind of on the fly,” he recalls. “Then I started creating my own curriculum, and it's been working ever since.”

His curriculum soon involved a choir. Initially, Tabone wrote music for the students to sing. They performed “wherever we could” around town, he says, including grocery stores, bookstores and the Capitol. In 2003, the Palm choir released a CD that featured Tabone’s compositions. The following year, they got a spot in the ACL Fest lineup.

Tabone switched schools in 2009 when the music teacher job opened up at Barton Hills Elementary, which was much closer to where he and his wife live in the Bouldin Creek neighborhood. At Barton Hills, Tabone began to steer the choir’s performances more toward the repertoires of well-known artists. This was partly because of continued ACL Fest opportunities.

“I like to feature music from people who are performing, so that’s kind of when that started — doing Wilco tunes, Flaming Lips tunes,” he said. “And kind of the same thing for South by Southwest. The choir gets these great gigs now and I don’t write hardly ever, because at all of our shows, the set is sort of dictated by what we’re doing.”

RELATED: Barton Hills Choir takes part in SXSW David Bowie tribute

Sometimes that leads to collaborations with the artists whose music they’re singing. In addition to the 2014 Belle & Sebastian cameo at ACL Fest, Flaming Lips leader Wayne Coyne invited the group to perform with his band at an ACL Live concert a couple of years ago. They’ve also sung at the Erwin Center with Pink Floyd leader Roger Waters.

In 2016, a project involving Grateful Dead songs ended up making the choir semi-world-famous, when covers of “Ripple” and “Touch of Grey” racked up hundreds of thousands of YouTube views. That eventually led to two volumes of CDs featuring Dead songs. “The good thing about the Grateful Dead is they encourage it,” Tabone says, noting that those big YouTube numbers came after the choir’s videos got shared on Dead-related social media pages.

But licensing can be tricky with cover songs, even for an elementary school choir. “People will donate money to the school,” he says, “and then we use harryfox.com, which is a mechanical rights company, to pay for all the licensing fees for the tunes.”

Here’s another novel thing about the CDs, though: They’re free. Anyone who attends the 3Ten Release show for “Rock the Classics” will receive a disc as part of admission. (The $10 cover helps cover the venue's production costs, a videographer and sound mixer, and the musicians who regularly accompany Tabone and the choir, including drummer Jake Perlman, bassist Jason Brint and guitarist Don Cento.)

It’s worth remembering that the Barton Hills Choir isn’t a traditional for-profit musical ensemble: These are school children who are simply taking part in extracurricular activities. As a result, you won’t find their CDs at Waterloo or other local record stores, or on streaming services such as Spotify. They mail out the CDs upon request, and AISD allows them to take donations of stamps for that purpose. They also give them away at out-of-town appearances, which in the past couple of years have included trips to Wyoming, Brooklyn and Chicago’s Wrigley Field.

At ACL Fest this year, the Barton Hills Choir will appear both weekends on the Austin Kiddie Limits stage: from 12:30 to 1 p.m. on Friday, Oct. 4, and from 11 a.m. to noon on Saturday, Oct. 12. Expect to hear songs by 2019 headliners Guns N’ Roses ("Sweet Child O' Mine"), Tame Impala and the Cure, as well as a couple of past favorites.

Just as the sets change every year at ACL Fest, so do the members of the choir. Tabone gives sixth graders priority for solos at the festival, but not everyone stays in the choir for two years. Sixth grade is typically part of middle school in the Austin district; Barton Hills also has a sixth-grade class, but some students move on to middle school after fifth grade.

“It’s difficult seeing a lot of choir members leave after fifth,” Tabone says. “Having said that, every sixth grade choir I’ve had at BHC has been fantastic, including this year.”

He notes that many of the choir members have been part of his music class since kindergarten. And when they leave, they’ll have more opportunities to participate through avenues such as choir camp, which is open to former as well as current students. And Tabone tries to stay in touch with alumni. He recently assembled a reunion show at ABGB featuring students from the Palm Elementary days who are now in their 20s.

In a few years, Tabone expects to welcome a rather special new recruit to the Barton Hills Choir. He and his wife had their first child three years ago. “She knows all the tunes; she sings all the time,” he says. “I honestly can’t wait. It’s going to be a lot of fun.”

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