Abstract : This research was conducted in the field of indisciplinarian Applied Linguistics, following an ethnographic methodological approach, within the in-service indigenous teachers training program Ação Saberes Indígenas na Escola (ASIE), created at a national level by the Brazilian Department of Education in 2013 and implemented in the state of Santa Catarina by UFSC between 2015 e 2017. Its main goal is to build theoretical alternatives for teaching-learning Guarani, Kaingang and Laklãnõ-Xokleng languages, reinvented as social processes, at school, aiming at strengthening the struggle of those populations. These theoretical alternatives are built upon discourses (of which audiovisual register is offered) uttered by teachers, chiefs and sages during the Great Meetings of ASIE in indigenous lands, as well as upon reflections on the material practices of those Meetings in which natural, easy, spontaneous and abundant utterance in indigenous languages was witnessed. To serve the interpretive analysis of those discourses and practices, the theoretical background (that relies primarily on Mikhail Bakhtin e Michel Foucault) focuses on discourse, languages and how control is exerted over them through procedures that aim at establishing rules, grounded on geographies and political economies of truth, in order to legitimate and favor certain discourses and utterers, highlighting the role of schools within this process. Afterwards, the discourses on languages favored by Western linguistic and philological tradition are questioned, chiefly those that represent them as autonomous systems of indestructible rules. Characterizing those discourses on languages as inventions that serve the purposes of colonial and neo-colonial political and economic domination, with particularly harmful effects on indigenous populations, it is discussed next how those discourses and harmful effects are kept alive still today in school practices, also in those of indigenous contexts. In order to contribute to change that situation, criticized by the participants of the research, a reinvention of languages is proposed grounded on David Harvey?s theory that describes social processes as consisting in the articulation of six interdependent moments, i.e., discourse, power, institutions, material practices, social relations and imaginary. Through the interaction between the theoretical background and the ethnographic data, generated throughout 34 months during which the researcher was in the field also as supervisor of ASIE at UFSC, the analysis is carried out around those moments and the categories strength, struggle, system, paper, time and space. Upon the reflection, grounded on those categories, on the material practices portrayed in literary-photographic tales, a theoretical alternative is put forward to teach-learn indigenous languages as social processes at school that consists in teachers and students getting involved, by virtue of the indigenous strength and struggle, in differentiated school practices of freedom, that is, practices whose guidelines are provided by the elderly and are developed in times-spaces that favor the strengthening of the coexistence, the practice, the orality and the shared movement of the elderly, teachers and students, as well as the believes, values and desires associated to those times-spaces and social relationships, within a hybrid temporality between the temporality of indigenous education and the temporality of school education.