In a cold and nameless town created by an Oakland author, a little girl named Annabelle knitted.

She knitted herself a sweater, then one for her dog, then for a friend, and then, and then and then — until everyone and near everything in town was covered in colorful yarn.

Sunday, on a very warm day, in the very real town of Petaluma, the author of "Extra Yarn," Mac Barnett, arrived on Kentucky Street to read his book to children and found, to his shock, that his story had escaped its covers.

An estimated 10,000 yards of yarn in dozens of colors covered everything from a stop sign to a metal bench, a potted plant to a bicycle rack.

Barnett and the book's illustrator, Jon Klassen, parked behind what appeared to be a 1970s Volkswagen Beetle — it was hard to tell; it was covered in a patchwork of yarn.

"We were blown away, I love it when the real world begins to mirror fiction," said Barnett, speaking after he and Klassen gave an afternoon talk that filled a room with over 60 people.

The spectacle was inspired by a burgeoning public art movement that might be considered a gentler offshoot of graffiti and is sometimes known as guerilla knitting, because it is generally undertaken by anonymous hands under cover of darkness.

In this case it took place in daylight and the perpetrators' identities were known: They were art students at Petaluma's Kenilworth Junior High School who put to good use cartons of yarn collected over the years and also donated by Knitterly, a downtown knitting supply store.

"It's not something you see every day," said Dennis Taylor-Warner, 14, a master of understatement who had carefully dressed the bicycle rack in yarn strands of burgundy and green, blue and purple.

He was one of about 10 students who engineered the project under the tutelage of teacher Erinn VanderMeer. A dedicated knitter, she saw in the event — which Copperfield's organized — a chance to engage some young minds.

"They get a chance to go out and do something that makes people look at something and think about it in a new way," she said. "It's not destructive and it brings a smile to people's faces."

The book reading also raised money for Jesse Paul, 27, a Petaluma man who suffered severe brain injuries in a July motorcycle crash on Highway 37. Twenty percent of the "Extra Yarn" sales for the day went to a fund for his care.

VanderMeer characterized the work as yarn-storming, rather than yarn-bombing, which the practice is often referred to as, because, she said, "I thought it was more PC for my junior high kids."

Taylor-Warner said he planned to storm on.

"Probably my bed," he said, when asked what was next to be covered.

You can reach Staff Writer Jeremy Hay at 521-5212 or jeremy.hay@pressdemocrat.com.