During the month of May in Pittsburg, multicolored stories ride on buses and decorate the streets and shop windows. Butterfly art and crazy socks add to the downtown vibrancy.

It is all part of the Pittsburg Library's month-long celebration of the city's beauty, a collaboration with Pittsburg Arts & Community Foundation and Tri Delta Transit.

"Pittsburg is in the process of revitalizing its downtown," Senior Library Manager Ginny Golden said. "There are restaurants, local businesses, a community park, a historic thriving theater and more. We envisioned this project as a way to connect the library with our community and schools."

San Francisco-based artist Christian Robinson will sign books and take part in the Pittsburg Library s StoryWalk event on May 21. Courtesy Anastasiia Sapon

Inspiration for the event came not only from Golden and her staff, but from "Last Stop on Market Street," the 2016 Newbery Medal children's picture book by author Matt de la Peña, with illustrations by San Francisco-based artist Christian Robinson.

The book won a 2016 Caldecott honor, a 2016 Coretta Scott King Illustrator honor, and was a New York Times Book Review Notable Children's Book of 2015, among other recognition and awards.

"Last Stop" tells the story of a boy, CJ, who travels with his grandmother on a city bus. Together, they encounter guitar-playing bus passengers, rundown parts of town, kids with mobile gadgets that CJ doesn't own, soup kitchens, butterflies and more. CJ asks a series of questions about disparity in the urban environment; his grandmother helps him to see beauty and to appreciate "a bus that breathes fire" over the seeming luxury of owning a car.

Diversity in children's picture books is a topic that gets a lot of play in current media, one reason for the book's popularity. Robinson's collage and paint artwork reflects society's broad palette, with people of all colors and economic status represented. But the underlying message wouldn't vibrate with such deep resonance without it being told in Peña's delightful, direct-but-light manner that never becomes pedagogical.

"I'm lucky, I get to select the stories that resonate and hold true to me," said Robinson, the book's illustrator. "A lot of time, the books come down the line of my personal experiences, which are largely urban."

Robinson will join a community event on May 21 to ride a bus, sign books and tour the StoryWalk where spreads of the book are posted on display in the windows of downtown businesses.

The 29-year-old artist grew up in Los Angeles and graduated from California Institute of the Arts before moving to the Bay Area to intern with Pixar Animation Studios. His work has been featured by the Sesame Street Workshop and includes award-winning books -- "Josephine," by Patricia Hruby Powell, and "Gaston," by Kelly di Puchhio, among others.

"For Josephine, the story of performer and civil rights advocate Josephine Baker, a woman who grew up in total poverty and by age 19 was traveling the world and living in castles, I took the advance money and left America for the first time," recalled Robinson. "It was me, a black American, discovering Paris just like she did."

During his childhood, Robinson and his older brother lived in a one-bedroom apartment with their grandmother, an aunt and two cousins.

"We had limited resources, but an abundance of love. And by drawing, I could control the world I wanted to see on a piece of paper. Whatever movie I saw, whatever real-life scene, I'd sit down and redraw it my way."

For all people, drawing is therapeutic, escapism, fun, Robinson says. He struggled as a young reader and speculates that books lacking diversity might have been part of the cause.

"Who knows? Maybe looking for yourself and not finding it, not seeing yourself makes you wonder if you're validated. Does your life matter? If you take on the belief that you don't, that's important. Seeing someone who looks like you, someone having an adventure, that's cool. I want to see an African-American battling wizards, something fun."

Golden says Robinson's illustrations are an accurate depiction of the Pittsburg community. "Seeing the people on his bus looked like they could have been drawn from our city bus. Pittsburg is a diverse community full of beauty and pride."

When visiting schools or speaking to kids about books, Robinson likes to tell them about mistakes. "I show them how many revisions I make. I tell them about how I keep trying until I get it right and I make sure they know how much work it is."

But more often, he talks about art being joyful, intuitive, and reflective of his "wild personal experiences" and the colorful architecture he appreciates in the Bay Area.

And he is no longer nervous in front of a crowd of kids. "Being an illustrator can be solitary, reflective. The contrast -- to share the work and see how kids respond -- it's recharging. I love making stuff with them and hearing their perspective."