In 2009, Todd Bol of Hudson, Wisc., had a brilliant idea to honor his mother, a bookworm and retired schoolteacher: He built a small model of a one-room school house, filled it with books, and stuck it on a pole in his yard with a sign that said “Free Books.” His little library became so popular that Bol built more and gave them to people to install in their yards. Eventually he teamed up with Rich Brooks of the University of Wisconsin, who had an idea to turn this effort into something much grander—a way to promote literacy nationwide, give people access to free books in communities where they’re hard to come by, and encourage more reading. They initially set a goal of building 2,509 of these birdhouse-like “Little Free Libraries,” the same number of  libraries that Andrew Carnegie supported at the turn of the 19th century. But in the past five years, they’ve far exceeded their hopes. As of this month, Little Free Library counts between 10,000 and 12,000 registered small libraries across the world, with more built every month.

On its website, Little Free Library offers instructions on how to build and maintain libraries using recycled materials, and for the less-handy, it sells libraries that are already built and ready to install.

Every year, more people and organizations become involved in the Little Free Library movement. For example, The United Way of Northwest Georgia recently undertook a project to build and install 25 little libraries, inspired by member Carey Mitchell’s outsized book collection that he wanted to share with others. While Little Free Library warns people not to install libraries in public places without permission, communities throughout northwest Georgia have embraced the idea, and 25 libraries will soon be installed in public parks and areas. Now they’re just looking for a few volunteers to help maintain the libraries, keeping them clean and stocked with books. Especially in towns where bookstores have closed or libraries are distant, these little beacons of literature are welcome additions to the landscape.