Inclusion is a widely discussed demand. But how can it be implemented in practice? This material offers you an inclusive teaching approach that engages all students. The booklet contains a brief didactic introduction, numerous copy templates with explanations, as well as appropriate diagnostic tests. Those who want to calculate confidently within the hundred range must understand the relationship between tens and units. Only those who recognize the decimal value levels as the foundation of our numbers can calculate ten transitions intelligently. The tasks in the booklet guide the children's focus on the "reversible ten" through the recommended calculation actions and their notation. Bundling objects like ten rods and coins make it particularly tangible to experience the ten boundary, especially during subtraction. Additionally, calculating with mixed units of measurement supports this learning process.