One of the most important didactic concepts in mathematics is the spiral approach. One of the first psychological theorists to propose a spiral approach was Jerome Bruner in his The Process of Education, published in 1960. The first part of this diploma thesis is focused on the conceptualisation of the principal of spiral approach. Fundamental for the development of this principle of education is Piagets stage theory. As a second step, essential aspects of Bruners theory of a spiral approach are delineated. Besides introducing fundamental ideas, the theoretical conceptualisations are transferred to practical exercises for math classes. Subsequently, didactic principles will be deduced from the essential ideas of the spiral approach. Ultimately, consequences and challenges arising from the application of the spiral approach as a teaching method will be outlined. At the end, a checklist will be included, in which each sequence of classes can be planned according to the spiral approach. The second part of the thesis consists of the didactic implementation of the theory from the first to the twelfth grade. The focus of the implementation is The Introduction of New Sets of Numbers. The spiral curriculum to be applied has been generated from a number of different school books and its exercises. The theoretical description of the materials to be learned and examples of educationally valuable exercises, which can be used to introduce and practice old and new subject matters, are presented. It was the goal of this diploma thesis to present teachers with a worked-out concept, the spiral curriculum, which serves to introduce various number sets in school taking into account the spiral approach.