Tavi Gevinson, reads on stage and demonstrates a variety of bitchfaces. (Instagram photo from Rookie Mag)

By the time Tavi Gevinson arrived at Littlefield in Brooklyn yesterday afternoon a full hour late (her plane had been delayed), the venue was packed with waify, whimsically dressed teenage girls in carefully considered outfits. There were some shrieks from the audience as the revelation that Ms. Gevinson had arrived spread around the room, and a few trembling “oh my god’s” were emitted as the 16-year-old editor-in-chief took the stage. Pink crepe paper streamers were strung along the walls and metallic stars were had been stuck around the stage. There were boxes of cupcakes on the tables and a few moms chatted in the background.

Ms. Gevinson read from her Rookie DIY article “How to Bitchface,” demonstrating each of the facial expressions discussed and drawing loud laughs from a generous audience. Her voice had an air of self-assured confidence and grace, which was a welcome change from the syrupy tone of the young Rookie writers who read before her, even when she slipped up on a few notes in the text. “Sorry, I should have looked over this more,” Ms. Gevinson apologized to the audience.

After the reading, which included novelist and Rookie contributor Emma Straub, and a performance by girl band Supercute, Rookie editor Amy Rose Spiegel invited the audience to “stay and dance with us, and mingle,” and put on what may have been the Grease soundtrack. Rather than dance, most of the audience formed a haphazard line to talk to Ms. Gevinson, who posed for photos with fans and signed autographs—even signing one girl’s copy of The Virgin Suicides, which Ms. Gevinson told the Times last year was one of “the two things in pop-culture that influenced me aesthetically the most,” the other being Twin Peaks.

Ms. Gevinson couldn’t remember exactly who had the idea for the Rookie Road Trip this summer, which is visiting thirteen states over the next two months, but told The Observer that it was something she and Rookie photographer Petra Collins had “fantasized about.”

“We had a survey on the site for people to say where they live, and except for a couple that are way out of the way, we’re going to the cities that have the most readers,” Ms. Gevinson told us.

“I’ve been wanting to start a blog for a really long time and Tavi is kind of an inspiration to me,” Isabella Adler, a 16-year-old from Los Angeles told The Observer before the event. “She’s cute. I’m completely jealous that she gets to go to all those amazing fashion shows. I want to have her life,” Ms. Adler told us candidly.

Chris Chudnovsky, the mother of a 12-year-old Rookie fan told us, “as soon as they said there was going to be a road trip, she printed it out and put it on her bedroom wall. She said we could go on vacation as long as we were around this day.”

Though for the most part the audience resembled a girls-only sweet sixteen party, some older readers turned out as well. “I’ve been reading [Tavi’s] blog since she was 11-years-old,” Paige Bradley, a 23-year-old art assistant told us. Ms. Bradley said that even though Rookie is targeted at teenage girls, “it doesn’t feel below my level.”

“I love writing for teenage girls. It’s my favorite thing to do,” Ms. Straub told The Observer after the reading. “I write for a lot of places but nothing is as satisfying as the stuff I write for Rookie.”

“For next month I wrote a thing about George Michael’s ‘Freedom,’ the music video from 1990 that I love so much… Nobody else will let me write about that, but Rookie will!” Ms. Straub explained. Her first novel, Laura Lamont’s Life in Pictures, is forthcoming this September.

Ms. Gevinson told The Observer that she’s been hard at work on Rookie’s first print edition, which should come out this fall. When asked what she’s currently reading, Ms. Gevinson explained, “I just went to the library with my dad and picked out The White Album by Joan Didion.” And though we weren’t blown away by her choice of outfit—a pleated leopard skirt and white blouse that could have been from Urban Outfitters, a corporate sponsor of the road trip—we can’t say that Ms. Gevinson doesn’t have good taste.