Sojourner and the other young poets met first lady Michelle Obama at the White House on Sept. 20. When I caught up with the 17-year-old a week later, she was still giddy.
"When she was talking to us, not only was she so genuine and warm, but she remembered specific things about each of our poems, and she was telling us what she enjoyed, what she didn't understand," recalled Sojourner, who attends Interlochen Arts Academy, a private boarding school in Michigan.
"She was really engaging with our work. So that was really powerful, to think that the first lady was reading our poetry and really absorbing to the point that she was remembering little details that even we had forgotten."
In a strange land
Born to a Philadelphian and a native Ivorian, Sojourner moved here with her mother and younger brother when she was 7, in 2002. Her father had died and civil war had broken out in the country.
They hoped to return once things simmered down, but ended up staying here, settling in at Sojourner's maternal grandparents' home.
Adjusting to life in Overbrook was a challenge. Classmates gave Sojourner the side eye when she showed up at school in traditional African garb. Same thing when she spoke French, one of three languages she speaks fluently.
Her neighborhood lacked the ethnic diversity Sojourner had been accustomed to while attending an international school in the Ivory Coast.
"A lot of people in my public school weren't used to people from other places, so I was always asked, like, really ignorant questions about me living in Cote d'Ivoire. They'd say, 'Did you wear shoes there?' 'Did you have running water?' I was bombarded by a lot of stereotypes that people have," Sojourner recalled.
"As I grew older, I realized that my poetry could be a means of breaking those stereotypes and showing the range of what Africa as a continent has to offer, and the fact that Africa is a continent - not a country. A lot of people forget that," she added.
Here's an excerpt from a poem called "I'm Not Without a Moon" that she wrote about a Malian-American friend:
"...But Cissé is my teacher.
She packs home for lunch
and even though she must make sure
the scent of her foutou [a banana dish], crushed and yellow,
doesn't arouse laughter,
she brings it anyways."
McBride, who has published two books of poetry, used to take her daughter to poetry readings at the now-closed Robin's Book Store. Owner Larry Robin remembered the duo fondly.
"Some of these kids at a very early age show real talent," Robin said. "She's lucky that her mother is artistic and supports her talent."
It wasn't until Sojourner was in the ninth grade at Friends Central, in Wynnewood, that McBride really got a sense of just how talented a writer her daughter had become. Listening to Sojourner read her poetry during a school event was an "aha" moment.
"She wrote a beautiful poem about Africa, what the stereotype was, and she would offer a counter to that stereotype," recalled McBride, who graduated from Cheyney University.
When Sojourner wanted more of a focus on creative writing than Friends Central offered, McBride allowed her to transfer to Interlochen, which attracts an international student body. Interlochen alumni include Norah Jones, Jewel and Jessye Norman.
"Prior to coming to Interlochen," Sojourner said, "I didn't consider myself a writer. I was just like, 'Oh I enjoy writing poetry,' and that's where it stopped.
"They were really, really good about making us submit, submit - submit nonstop [to literary publications]. They were like, 'Your work is good. You need to get it out there. It's not for sitting on. It's for people to react to and engage with,' " she added. "That's the moment where it sparked in my mind that 'Wow, I'm a writer.' "
Instructors encouraged her to enter the highly competitive Scholastic Arts & Writing Awards. The five National Youth Poets were chosen from among medalists in the awards competition.
Sojourner snagged a gold medal - the very one that the first lady pinned on her last month.
"It was such a surreal feeling," Sojourner told me afterward. "Just to be in the same room with her was just surreal. After it happened, I kept asking myself, 'Did that really happen?' "
Sojourner is applying to colleges now, including Princeton. When she told Michelle Obama that, Sojourner said, the first lady, a Princeton grad, did a little dance.
On Twitter: @JeniceArmstrong