The purpose of the study is to substantiate factors of optimising the methodology for teaching foreign languages at school in the context of the theory of bilingual consciousness formation as goal setting. The article analyses the practical purpose of teaching foreign languages at school from the perspective of anthropocentrism, justifies rationality of developing the methodology for teaching foreign languages at school taking into account patterns of bilingualism formation and suggests factors of optimising the foreign language teaching methodology. Scientific novelty of the work lies in considering the goal of teaching foreign languages at school in the context of the anthropocentric paradigm and theories of bilingual consciousness formation, as well as in substantiating factors of optimising the methodology for teaching foreign languages at school taking into account bilingualism formation laws. As a result, it has been proved that transition to the formation of subordinate bilingualism as a stage of bilingual personality development in the process of teaching foreign languages calls for optimisation of the methodology for teaching foreign languages.