Information about the series: "Mathefreunde" is based on the requirements of educational standards and current curricula. It combines the practical experiences of teachers with the latest findings in elementary school didactics. The concept of "Mathefreunde" ensures the successful development of fundamental mathematical competencies in all children. The teaching material consistently employs differentiation, independent work with self-assessment, and reinforcement through practice, repetition, and application. The components of "Mathefreunde" comprehensively cover the learning areas of arithmetic, geometry, and measurement. Problem-solving is a constant element. Additionally, content on combinatorics and data, frequency, and probability has been included. "Mathefreunde" demonstrates many additional strengths: Differentiation: All tasks are presented in three levels of differentiation.