Courtney Marie Andrews is a freak among us. Where most teenagers have suffered through the agony of reading book reports in English class — sweat forming on the back of necks as they stumble through Twain, Fitzgerald or Salinger — Andrews started writing songs at 13 and began gigging a few years later. The indie-folk songwriter even had her first well-received album out (2008’s Urban Myths) by the time she was 18.

But even Andrews is still confused by how she did it. Onstage, she was willing to open her soul up to the world, yet she insists that in the day-to-day schooling grind she was a nervous wreck — just like the rest of us.

“I would definitely say I’m much better at getting in front of an audience and singing as opposed to talking,” she says, “When I was 14 or 15, I was one of the kids in class who was really afraid in front of people.”

Despite being the runt at the music venues around Phoenix, Ariz., Andrews’ wide-eyed innocence made her impervious to feeling like the outsider among older musicians.

“I’m sure it seemed weird to other people, but it didn’t seem weird to me. ’Cause when you love to do something you don’t really think about it. You just do it because it’s what you know.”

Andrews’ sound has grown fuller and richer over the years. She says her music’s evolution actually has nothing to do with how she sings or plays, but rather how she senses the music around her.

“When you start to know what sound is. You can’t really hear things well. You can’t really make out differences.”

Andrews upward career trajectory has also coincided with a boom in the popularity of indie folk. And while Andrews acknowledges the genre’s rise, she say that she doesn’t waste any time dwelling on it.

“I never really think about that,” she says. “You kinda just make the art you feel you need to make. Some years it will be popular, some years it won’t, but you have to be true to yourself and true to your art or else no one will like it.”

She speaks from experience.

Andrews’ tunes caught the eyes of another group of musical Phoenicians: Jimmy Eat World. The famed rockers became so enamored with Andrews that they invited her to sing backup vocals on a number of tracks from their 2010 album, Invented. The band then dragged her out on tour, where Andrews experienced the sudden jolt of performing in front of a huge audience.

“It was wild. I’m used to playing in half-empty bars.”

With the big-stage experience in her back pocket, at just shy of 21 years old, Andrews hunkered down to record her fourth album, No One’s Slate Is Clean. For the first time ever, it was really a full band experience.

“Playing songs with a band, you kinda have to change some things around to make sense for the whole band,” she says. “You also have a few more ears coming into it, hearing different things, which helps.”

Andrews may still look like a fresh-faced newcomer, but the girl’s got the chops to hit just the right heart-string-tugging notes.

Courtney Marie Andrews plays with Dillon Warnek • Thurs, Jan. 12, at 8 pm • The Belltower • $7 • All-ages • belltowerpullman.com • (509) 595-0546