With this workbook, children can train and improve their arithmetic skills and mathematical thinking. All areas of the curriculum, such as number range expansion up to 1000, basic operations, word problems, geometry, measurements, probability, and combinatorics, are presented in child-friendly and diverse tasks, making learning enjoyable. Loving illustrations illustrate the exercises. The math monkey Coco motivates students with helpful tips. A removable answer key serves for checking, enabling independent learning.