Tasks play a central role in the classroom. They help to explore the material, guide through textbooks and workbooks, and structure the lesson. Task cultures vary from subject to subject, yet they share commonalities that can be found, more or less unchanged, in every subject. This is where the task book comes in. It claims to have cross-disciplinary validity in many respects and aims to provide concrete guidance for every teacher, both in the reception and construction of tasks in everyday teaching. In the first part, the task book informs about the functions of tasks in the classroom, eight practice-relevant quality characteristics of tasks, the relationship between task culture and competency-oriented teaching, as well as ways to individualize teaching using tasks.