In this paper, the aim is to discuss some contemporary challenges to the formal education in the vernacular in high school, considering the monologizing tendency of what is understood as engagement in digital social media. The "fuller participation of young people in the different sociocultural practices that involve the use of languages" provided for in the Common National Curriculum Basis (CNCB) is assumed as a motto for problematizing the latent contradiction between what, in common sense, is understood as "subject's discourse" and what, from a dialogic point of view, is defined as effective sociocultural participation, which installs subjects of discourse. The discussion is based on what has been called Dialogic Discourse Analysis and is developed in two main blocks. The first constitutes a brief essay on the social-historical primacy that underlies the theoretical framework mobilized to define what is meant by language, concrete utterance, and subject of the discourse. The second block is a speculative refletion by means of which it is compared, on the one hand, contemporary practices of digital social media engagement and, on the other, the challenge for formal education to contribute to the responsible social interaction of young people in those practices. The articulation of these two blocks demonstrates how taking distance from common sense about what is meant by "to interact socially" indicates enunciative-discursive mechanisms for effective cultural participation. Thus, it is concluded that the CNCB for the vernacular in high school is not a prescriptive guidance, but a propositiontal guideline that aims at the ethical commitment of the actors implied in the formal educational sphere.
