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.

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

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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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