Cello students practice at City Strings United.

Twelve rental instruments, a teaching space courtesy of Twelfth Baptist Church, and one handdrawn logo were all that composer and cellist Bithyah Israel was working with when she launched City Strings United, a nonprofit offering free music lessons to children in Roxbury.

Founded in 2012, City Strings offers lessons in piano, violin and cello to children ages four to 18 and seeks to fill a gap for accessible music education in urban Boston. Everything is free aside from a $25 annual fee, which can be waived due to financial need, said Israel.

“You just don’t see representation of a lot of our communities on stage that often,” Israel said. “So there still is a need to elevate the young people in our communities [and] we need to bridge the gap to access to opportunities.”

Boston-born Israel, a cellist of 30 years, said her parents couldn’t afford music lessons, but she received free cello lessons as a child from a cellist in the San Diego Symphony Orchestra. Learning to play cello “really opened a world of possibilities,” Israel said, as she went on to become an independent cellist and performer.

Her lived experiences inspired her to found City Strings, Israel said, as she “felt a desire to help more kids get access” in the same way she did.

“I feel like playing music is a skill like reading,” Israel said. “You can pay to get tutored. But it’s really a free knowledge.”

After returning to Boston from San Diego, Israel searched for a community music program she could volunteer with but couldn’t find anything.

While she initially disregarded the idea to launch her own program from a church friend, she later found herself inspired by City Lax, a documentary about young people in the Denver Metro area who had no previous experience with lacrosse yet went on to become state champions.

“During the final game, I was yelling at the TV like it was the Super Bowl,” Israel said. “I was just like, ‘These kids have to win.’”

That evening, she sat at her kitchen table and drew the logo for City Strings United. Another friend from church donated money, which she used to rent instruments from a store in Newton, and she asked the historic Twelfth Baptist Church if she could use their space to offer free cello lessons.

Over the next two Sundays, the church announced Israel’s lessons and soon there were 12 kids signed up for the pilot program.

Among the inaugural members was Alexia Martinez, who started learning at City Strings when she was in the second grade. Now, 14 years later, she has returned to the organization as the program assistant and lead arts administrative apprentice.

“I enjoy giving back to students who kind of remind me of myself, in the way that they’re young urban kids,” Martinez said. “It’s adding so much to their experience as a young person that lives in Boston because some of those opportunities aren’t always afforded.”

While in the fifth grade Martinez moved to Norwood, a suburb of Boston, where she said the schools offered band, orchestra and choir. Martinez said there was”none of that” in her previous school district in Dorchester.

“It showed me as a young person that in different communities, there are different opportunities for people, and those people look different,” Martinez said.

The opportunity to learn an instrument is “not as prevalent in the city” as it is in the suburbs, Martinez said.

“I think it’s important for our young people in the city to know that they are capable of playing something like a classical instrument, even though they may not be in a financial position or in a good location to have that opportunity,” she said.

Aisha Payne, whose children Amelia and Royce attend City Strings, said the organization has “opened up a different avenue” for them. They learned about City Springs at a community event at Twelfth Baptist Church where parents were invited to sign up their children for free lessons on the weekends.

“The cello and the violin, I don’t really know where they would get those opportunities if they weren’t a part of City Strings,” Payne said.

Daughter Amelia, 11, has been learning cello at City Strings since she was seven, while Royce, nine, has been learning the violin there since he was six. Payne said she enrolled Amelia in private cello lessons last year after seeing that she was “really into it.”

“But we wouldn’t have been able to do private lessons if we didn’t have the access to do the free ones first,” Payne said, adding that Amelia gets to use the instruments she receives from City Strings for her private lessons.

What began with just 12 students and one instructor today builds community for 11 instructors and over 100 students. Looking forward, Israel said she hopes the organization can expand its reach even further.