HUDSON, Wis. (AP) — A Wisconsin man planned a simple tribute to his mother when he put up a miniature version of a one-room schoolhouse, filled it with books and invited people to borrow them.

But Todd Bol’s neighbors began dropping by so often his lawn became a gathering spot. After a friend put out similar boxes in Madison and got the same reaction, the idea really began spreading.

Three years later, the whimsical boxes known as Little Free Libraries number in the thousands and have spread to at least 36 countries.

Some schools have seized on their potential, often erecting the tiny libraries in poorer neighborhoods where kids many not have many books at home.

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