Donald J. Sobol’s pint-sized amateur detective has been a hit with young readers for over three decades. For 25 cents a day—plus expenses—Encyclopedia Brown will solve any case, big or small for the kids in his neighborhood. He also secretly works with his police chief father to crack the toughest investigations and keep the streets of Idaville safe. Here are 10 more beguiling mysteries that will have listeners scratching their heads.