The study substantiates the theoretical and methodological aspects of modeling the educational environment in the professional and pedagogical activity of a general secondary education teacher on the methodological basis of the humanistic-competence paradigm of general secondary education and the concept of the New Ukrainian School. The article’s purpose is to clarify the role and significance of the modeling method as a means of efficient professional and pedagogical activity of teachers in the educational environment of general secondary schools. The principles of individualization of educational services, conscious perspective, flexibility of educational influences, democratization, and dynamism of the educational process are emphasized in the process of applying the modeling method by the teacher. The objects of modeling in the teacher’s activity are model programs in teaching subjects, a system of aspect and subject lessons, a set of club activities, individual qualities and properties of students’ personalities, etc. The author proposes the stages of creating a pedagogical model and the algorithm of modeling in the teacher’s activity (setting a goal, selecting an object, formulating a subject, clarifying the normative support, choosing a theory that explains the content of the subject of modeling; substantiating the basic assumptions of simplifying a real object; constructing a model using theoretical foundations; model examination; studying the model using a pedagogical experiment; finalizing, adjusting and finalizing the model). It is concluded that the awareness of the principles of building a model of the educational environment of general secondary school, as well as the use of this knowledge as a theoretical basis for the general scheme of forming the content of the educational process will contribute to the successful implementation of efficient professional and pedagogical activities of teachers in an institution aimed at building a health-developing educational space.