Step by step to more routine in mathematics lessons. In primary school mathematics classes, memorization is becoming increasingly important. When children memorize the results of addition and subtraction problems within the number range up to 20, lengthy calculations are no longer necessary, allowing for the resolution of more complex mathematical content. This volume achieves this without rote memorization. It focuses on automating the practice of basic mathematical operations. Playfully and with a lot of fun, students practice addition and subtraction in primary school mathematics classes, thereby building a solid foundational knowledge. The volume offers both individual tasks and partner tasks, as well as assignments for the entire class. It provides a variety of working materials for mathematics lessons. With this volume, you will receive numerous worksheets as photocopiable templates.