Inside, Grammer addresses a group of about 15 young people who are serving time: "We would like to reflect on what is it that makes a friend for you, what breaks a friend for you."

Class discussions can get serious. There's talk about drugs, gangs and death. Then, Grammer guides participants as they write about their life -- often incorporating music beats and poetry.

The workshop is part of Grammer's nonprofit, New Earth, which has helped thousands of at-risk youth transform their lives through arts-based programs.

"These kids get labeled young. And it's hard to pull themselves out of that," said Grammer, who founded the L.A. nonprofit in 2004. "We're doing everything we can to keep them out of the adult system. That's what drives us."

The group works in detention centers seven days a week, promoting literacy, reading comprehension and critical thinking. Every year, more than 1,800 incarcerated and formerly incarcerated youth in Los Angeles County are offered New Earth's programming.

"Recidivism has been a big problem in Los Angeles," Grammer said. "That is one of our main points of the work that we do -- to reduce recidivism in Los Angeles, to make sure kids do not end up back in cuffs, do not end up back behind bars."

For Grammer, the work -- and his connection to these young people -- is personal.

At 16, he was arrested and sentenced to five years on juvenile probation. At 18, he became a father, and at 21, he worked three jobs to make ends meet. After turning his life around, Grammer was determined to find a way to share his experiences and help keep young people from making the same mistakes he had.

"I think there's a certain point where you need to soul search," Grammer said. "I found that through poetry. I found that through music. I found that through writing. My life began to change."

In 2015, he opened the New Earth Arts and Leadership Center, which provides free programming and support services for people in the community ages 16 to 25. Some are at risk of dropping out of school; others sign up simply because they need some extra support. In addition to a music studio, there are field trips, counseling, vocational training and classes as part of a high school diploma program.

Grammer's group works with about 500 young people every week.

CNN's Allie Torgan spoke with Grammer about his work. Below is an edited version of their conversation.

CNN: Your nonprofit has evolved to incorporate so many programs. How do you measure success?

Harry Grammer: The ultimate goal at New Earth is that we have a young person free from system involvement, they get their high school diploma, they're ready for college, to be placed into a job. Those are our markers. When we know someone's reached those points, we know we've done our job.

New Earth covers a lot of ground because kids cover a lot of ground and we have to engage them. Every one of them has something unique they express. We've got to change the perception of how society sees them as well as helping them see themselves differently.

F.L.O.W. is our flagship program -- an acronym for the Fluent Love of Words. We teach F.L.O.W in camps, in the community and in our school. (It) is a creative writing, spoken word, poetry workshop, and helps them to explain and talk about and express their lives in writing. Young people get an opportunity to really get in there and look at events that have happened in their lives and begin to break those apart, write them, turn them into poems, turn poems to songs and turn songs to recordings.

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CNN: Some of the kids you work with have not been in the system. How do New Earth participants find you, and you them?

Grammer: The young people we work with are from all over L.A. But specifically, most come out of South Central L.A.

Many have been incarcerated and have been through juvenile justice or foster care. I've met some on the inside, meaning juvenile detention. There's also young people that have been referred by probation. Also people that have just walked in and said: "You know what? I think your program would be right for me."

No matter if we met them on the inside or they walked into our center, we do whatever we can to get them to the finish line.

CNN: How far will you go to help a kid?

Grammer: We meet them where they're at. If a young person can't get to us, we will drive to their house. I've had dinner at the kitchen table with families while we've all discussed family issues and problems.

We go to court. If there's a young person who is going back to court to visit their judge for a violation or if they're going to see if they could be released from probation, myself, our case workers, we will meet them in court, stand up in court, speak to the judge, advocate for them, let them know the progress that the young person has gone through while in our program. Judges have seen that this program really works and can be an alternative to incarceration.

Whatever is necessary to keep them out of the streets and somewhere that's productive, something that's going to nurture them and nourish them, is what we're all about.

Want to get involved? Check out the New Earth website and see how to help.

To donate to New Earth, click the CrowdRise widget below.