In a South Austin studio that feels more like a chic garage, women are seated in a circle strumming their way through the chord changes of Janis Joplin's "Mercedes Benz." "Oh, Lord, won't you buy me a Mercedes Benz?" they sing as Mandy Rowden calls out chords: D, A, G.

This is the third week of Girl Guitar's beginner class, which takes women from not knowing how to hold a guitar to performing at a showcase in a local music bar in six weeks.

"Are we breathing?" asks Rowden, the founder and teacher of Girl Guitar. "No? At least we're honest."

She shouts encouragement, often laced with expletives. This is, after all, a class for women, and adult beverages are served. "I want it to be fun," she says.

"You all were (expletive) strong! You did it!" she says after they finish multiple rounds of "Mercedes Benz."

"You all are so bad (expletive)!" she tells them.

She guides them through how to practice, how to go over the difficult chord changes again and again so they don't tense up when they know a hard one is coming. Instead of saying that guitar isn't for them when they're struggling, Rowden tells them, "You suck it up and do it again."

As they practice, she reminds them, "Don't forget to smile. Do you remember how much fun we're having?"

Rowden started Girl Guitar in 2007, really as a way to pay her cellphone bill. She had been teaching violin and piano lessons mostly to kids in Austin for a long time. "It was neat but taxing. I got burned out."

She had moved to New York in 2006, but after a few months of not making it, she moved back to Austin. "It was a total low point," she says. "My cellphone got cut off."

She decided to offer a one-time women's guitar class, she says, "just to get my cellphone turned on." She connected with people on MySpace who lived in Austin and listed music as an interest.

She says she put about three seconds' worth of thought into starting Girl Guitar. "I paid my phone bill, and the rest is history," she says.

With that first class of eight women, "We just had a good time," she says. After that first six weeks, everyone wanted to do it again, and they brought friends. She added more and more classes. By 2009, she could quit waiting tables and just run Girl Guitar and be a full-time musician.

"It was such an exciting thing when I realized this project has legs," she says. "I wasn't stuck in the service industry forever."

At one point, Girl Guitar expanded to Nashville and added more teachers, but Rowden missed being able to assure the quality of the classes.

Now women can take everything from beginning guitar to songwriting to rock classes. They can join a band with a theme. On Monday nights after the beginner class sings and strums "Mercedes Benz," a band of women work on the music of ZZ Top. Girl Guitar has even expanded to coed bands.

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Rowden found her own solace in playing guitar. As a child growing up in College Station, she played classical violin in the school orchestra and was very serious about it. When her family moved out to Sulphur Springs when she was 13, there was no school orchestra. "I lost my way," she says. "Everything is real dramatic when you are 13. I lost my sense of identity."

She started playing guitar. "I wanted to join Weezer," she says.

For college, she was a violin major at Texas A&M-Commerce before transferring to Texas State. "Then I discovered the fun of playing in bands," she says.

What she notices about teaching women is that "women are so much more forgiving of themselves," she says. "I find that in this situation women are a lot braver and more willing to jump in headfirst and make mistakes and laugh it off. Men tend to be harder on themselves, and it's more painful to mess up in front of other members. There's more ego involved."

Lindsay Mabry joined the beginner class on impulse, she says. Now her family knows that Monday nights are for her. "You're such a giver when you're a mother. ... You have to do something for yourself," she says. "I love music. It's such a spiritual experience for me."

Lara Davis bought herself a Girl Guitar class for her 40th birthday. Learning to play guitar was something she had put off, but now, she says, "It was fun."

Mabry says this is teaching her to not be so "hard on yourself," she says. "I've had to learn to be more forgiving of myself," she says.

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They say they love the supportive nature of the group. Everyone is trying to figure it out together, including what they're going to play in the upcoming showcase, an all-day event at a local music bar in which all the classes and band play.

Lorna Gardner says she didn't know about that until after she paid for the class. "If I had seen it, I would have passed," she says.

Robyn Teltschik is preparing for a large crowd. Her dad, she says, "called everyone in my family."

For Mabry, she's setting an example for her kids, who are 6 and 9. "I want them to see I'm practicing," she says.

After the six weeks are over, the members of the beginning guitar class can move up to the next level or take the class again. "It's really self-guided," Rowden says. "It's not like school where you repeated 10th grade and people make fun of you."

Sometimes people jump into joining one of the band classes and pick up a different instrument. "If you started to start a band on your own, it's an insane amount of work," Rowden says. "Here, you get to walk in, and it's all taken care of and you get to play." 

"There's no pressure to come into Girl Guitar and need to be a pro," Rowden says. Sometimes women want to learn to play guitar so they can play for their kids. Some just want a night away from the kids, she says.

What's she's found is that adults need bite-size chunks with a beginning and an end, Rowan says. And that end is the showcase.

Some students have gone on to form their own bands or become songwriters. "It makes me insanely proud," Rowden says.

As the ZZ Top group gets plugged in, Rowden accompanies them on bass. "Girls, that's fricking great!" she says.

Later, "It's coming together."

Jessie O'Connell on rhythm guitar is trying to figure out a new passage. "I sound so much nicer at home," she says.

Rowden reassures her. "There's a huge difference between what I sound like here and on my couch," she says. "Jessie, it's an experience thing. This is how we do it. We just launch back in and get experience."

Many of this group of four rockers started out taking the beginning guitar class and now have picked up drums or vocals or electric guitar. They've played in multiple genre bands at Girl Guitar.

One of the things they like is that Girl Guitar sets it all up and they just have to show up. They know their band members will show up, too, because they've paid to do so.

"I came to hang out," says singer Jocelyn Mellberg.

Erica Moss, the lead guitarist, says this works with a full-time job and that Rowden and all the bandmates she's had at Girl Guitar are "so supportive."

The level of support "is really so cool," Rowden says. "It's everything from being kind and cool and gracious with each other when someone is having a hard time with the music itself" or being supportive through marriages and divorces, babies born, illnesses and family tragedies. Longtime friendships have been formed here.

"It goes way more than just the music," Rowden says. "It's about the community. You play music together, you're automatically bonded."

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