Dave Eggers and Ninive Calegari, the co-founders of 826 National, thought they had found the perfect spot for their drop-in writing center. There was just one problem: The storefront space on Valencia Street in San Francisco's Mission District was zoned exclusively for retail. So Eggers, the celebrated writer, and Calegari, a veteran public-school teacher, got creative. They opened their tutoring center—inside a pirate supply store.

Opened in 2002, the pirate store—which stocks antiscurvy medicine, eye patches, and mermaid bait alongside computers, desks, and books—has been followed by Brooklyn Superhero Supply, the Greater Boston Bigfoot Research Institute, and similarly whimsical establishments in five other cities. The organization also provides in-school writing programs, field trips, and other services. All told, it has worked with 24,000 students, many of them from low-income communities, and built a network of 5,000 very passionate volunteers.

The idea, says Calegari, is to create an environment in which students can get the individual attention that is not available in overcrowded classrooms, while providing them with fun projects that can spark an interest in creative writing. "We see 826 as an opportunity to support teachers by bringing in the community to help them," she says. "Even with the best teachers, there's a huge gap between how much attention they would like to give their students and how much attention they are actually able to." Gerald Richards, who joined 826 National as CEO in 2010 after leading the Bay Area Network for Teaching Entrepreneurship, puts it another way: "What kid can pass up a superhero supply shop or a pirate store?"

Each of the eight chapters is run independently but receives fundraising support from and follows the overall model of the national organization. Most of the funding comes through corporate donations, grants, and a slew of fundraising events. Retail sales also bring in a small amount of revenue. In 2010, the organization ran on a budget of about $5 million.

In a recent study of three centers, 826 found that 51 percent of students who had completed the program improved their scores on a standardized written-language assessment. 826 has also published dozens of anthologies of student work, including Thanks and Have Fun Running the Country, a selection of kids' letters to President Obama. The group has received requests from organizations throughout the U.S. looking to start a chapter in their cities. Richards would eventually like to see 826 open one or two chapters per year. "I think the need is huge right now," he says, "so the sky's the limit."