5 1 50 Kumon Publishing Primary Author mixed material 9781935800422 north america Kumon Publishing 2012 images_%281%29.jpg.jpg Lower Elementary 6-9 Dale Gausman Additional Author NAMC Primary Author mixed material Hoboken, NJ Innovative Kids 2006 cover_math-1-lower-elementary-6-9-20240619133349.jpeg Richard Michelson Primary Author Leonard Baskin Primary Author mixed material 9780761450702 Marshall Cavendish Children\'s Books 2000 cover_ten-times-better-20230202135950.jpg Ruth Metterns Additional Author mixed material 1852700297 London Octopus Publishing 1987 Ruth Merttens Additional Author Colin Mier Additional Author mixed material 1852700041 London Octopus Publishing 1987