Mathematical linguistics, as a new methodological trend in linguistics, is of considerable importance also for pedagogy. It concerns especially the didactic of language teaching (whether the teaching of the mother tongue or of foreign languages), and an exact description of a certain language as well as of the learners’ means of expression is a valuable contribution to this didactic. We can even consider the possibility of using new linguistic approaches in the actual methodological processes in language teaching, e. g. in determining syntactical relations in a sentence. In this connection the author deals with the significance of the algebraic theory of graphs, the principles of generative grammar and the formalized description of the sentence in Danes’s conception for these purposes. However, a satisfactory solution of the problems involved with regard to the didactic aims is a difficult task, which requires co-operation between linguists and methodologists and also experimental verification. Positive results would help to make school parsing more exact and to elaborate the connection between linguistic training on one hand, and the teaching of mathematics, technical subjects and natural science on the other hand. In other words it would meet the demand for polytechnical modernized education. An exact description of the pupils’ linguistic media as well as that of linguistic expressions enabling the passing of information in teaching in general is important not only for the didactics of all the subjects in which the subject-matter is being presented by means of the natural language, but also for the development of the theory of education which aims at defining the teaching process as part of informational or more broadly cybernetic phenomena.