At this month's South by Southwest Music Festival in Austin, Texas, conversations among music fans sometimes began this way: "Hey, I saw a Philly band called ______. What's their story?"

The name of one Philadelphia act was the one most frequently filling in that blank.

That would be the Districts, the barely-out-of-high-school foursome fronted by singer Robby Grote, 19. The rising band from Lancaster County played SXSW in support of their self-titled five-song EP. They're now in the midst of a two-month national tour that comes to a close at the Sellersville Theater in Bucks County on Wednesday.

"It was good," said Grote, who, along with his bandmates, moved from Lititz to North Philadelphia last spring with the intention of going to Temple University. That changed when the band's career kept gathering momentum, and they decided to pull out of school three weeks before classes started to focus on music.

Of SXSW, Grote said, "It was definitely a little hectic: Seven shows in four days." He spoke on the phone this week as the band finished breakfast in San Diego and got ready to drive to Phoenix to play their next show. "Intense, kind of like jumping into cold water. But not too bad for our first time."

Highlights of the festival for the Districts included playing prestige gigs at the Spotify house, and at a Rachael Ray party before a "weird triumvirate" of celebrities that included Ray herself, Philadelphia blues-rapper G. Love, and Green Day bass player Mike Dirnt. "And just having the experience of being seen by the press people and the promoters from around the country and in Europe," Grote said. "It's awesome to win over people like that."

It's tempting to call the Districts a "baby band." Members range in age from 18 to 20. At their gig in San Diego, they had to load in their gear, and then exit the over-21 venue until they hit the stage so as to not violate California liquor laws. At SXSW, they were in competition with Irish teenage '60s-throwback rockers the Strypes to be the biggest baby-faced sensation of the festival.

But on stage, with a confidence that doesn't come easy to veteran acts, the band put across its impressive mix of raw rock-and-roll and quieter folkish elements. In part, that's because, despite their youth, the Districts are a seasoned unit that has been playing together for almost five years.

"We started in early high school," said Grote, who first got serious about guitar in fifth grade. "My older sister was really into punk rock. So when I was in elementary school I got exposed to the Sex Pistols and the Ramones. Then I guess I gradually found the bands that influenced the punk bands, like the MC5 and the Stooges."

Grote is the principal songwriter of tunes that are fleshed out by fellow band members Conor Jacobus (bass), Mark Larson (guitar), and Braden Lawrence (drums). "I write the lyrics that are the basis of the songs, usually with just an acoustic guitar," Grote said. "And then it's definitely a collaborative thing that gives it the full dynamic range of what it becomes in the end."

When the band first got together, Grote said, "we definitely clashed a lot about our opinions on music. When we started, we were playing a lot of covers. Some of us felt really strongly about playing 'Orange Crush' by R.E.M., and others were, like, 'I hate that song!' And then some of us wanted to learn 'Kick Out the Jams' by the MC5, and Conor and Mark sat out for that song, and me and Braden played it without them," Grote recalled, laughing at the memory.

In 2012, while still students at Warwick High School in Lititz, the band performed their song "Funeral Beds," which was included on their self-released full-length debut, Telephone (and also on their new EP), before cameras at HotBox Studios in South Philadelphia.

The studio owner, Matt Smith, posted the clip on reddit - twice. The first time, it was popular, but the second time, magic struck. Just as the band was getting ready to play WXPN-FM's Xponential Festival last July, "Funeral Beds" went viral on reddit and wound up on the front page of the Huffington Post.

Along with the band's energetic live show, that clip, now viewed more than 300,000 times, led to a label bidding war that resulted in the Districts signing with boutique Mississippi indie label Fat Possum in November.

Producer Bill Moriarty, who has worked with Dr. Dog and Man Man among many other Philadelphia bands, has recorded a dozen songs with the band as they work on their Fat Possum debut, which will most likely be released in the fall.

His first impression came from the "Funeral Beds" video. "They love what they're doing, and they're tight as a unit," he said. "And it's compelling musically. I think that's the reason they're taking off. As soon as they start singing, you see everybody look at their friends. It's like, 'Oh my God, are you seeing this?' "

Moriarty started working with the Districts in September, first in his East Falls studio and then at Kawari Sound in Wyncote. Grote, he said, "is such a compelling singer that you believe him, when you don't even know what the lyrics are.

"There are a lot of peculiar things about this band. They're very young. It reminds me of really early Modest Mouse in the way that they're tight. They're all playing with each other, but the tempos are all over the place. They're speeding up or slowing down, but they're all doing it together. It's like a family. . . . And there are a lot of bands that are rehashing the '60s or '70s, playing Americana or folk-rock. I don't get that sense at all with the Districts. They're discovering something that's new to them."

The Districts will tour Britain later this spring and play U.S. festivals this summer while continuing to work on their full-length CD for release in the fall.

Grote said his parents were "pretty cool" about his skipping college to pursue a career in rock. "I think my dad was pretty nervous: 'Make sure you're making the right decision!' But I have a mom and a stepdad, and a dad and a stepmom, and they all like the music, so it definitely helps that they believe in us. And being able to tour in California is much better than having to take midterms in March."

The Districts, with Keepers, play at 8 p.m. Wednesday at the Sellersville Theater, 24 W. Temple Ave., Sellersville. Tickets: $15-$25. Information: 215-257-5808 or