Information on the title: Workbooks with tasks for training, application, and networking; concise presentation of knowledge; a grade level test and solutions for self-control. Information on the series edition: Understanding mathematics sustainably. A perfect fit with the core curriculum. The new edition for North Rhine-Westphalia combines sound experience and current research findings on differentiation and diagnosis. The exercises are structured and differentiated even more comprehensively. Diagnostic tests supplement the chapters and contain additional exercises directly in the student book. Didactically complex tasks promote process-related and content-related skills. This leads step by step to a sustainable understanding of mathematics. A well-structured set of tasks trains the application of new content. Colours and symbols clearly indicate three different levels.