In this essay, I revisit the notions of 'informal education practices' and 'formal education practices' taken in their generic sense. After remembering the meanings commonly attributed to both terms, I reflect upon them specifically as fulcrums of mother tongue learning. Since they are direct or indirect participants in the daily social practices, we learn the discourse genres associated with them. With them, we learn not only the rules of language but also the differentiation potential of living languages, which foil the petrifying power of rules. Nevertheless, when mother tongue becomes a school subject, its differentiation potential becomes an anomaly to be corrected or cured. It has always been so all through the whole history of the formal education of the Portuguese language in school institutions.
Informal education practices; Formal education practices; Mother tongue mastery