Recent protest movements (yellow vests, pension reform and subsequent transport strikes, climate change…) have brought to the fore, in a context of information profusion linked to new dynamics in information circulation, the issues of misinformation, alternative facts, and so-called fake news (Vanbremeersch, 2018). At a time when people have less confidence in media and institutions, teaching information-documentation is a challenge for teachers and teacher librarians concerned with critical information culture. When there is easy access to all kinds of content, when there is a strong emphasis on storytelling and emotions, this calls for reconsidering the concept – and the approach – of information culture, in a broader and strong sense (Hollis, 2019; Paul, 1981). Information education has for a long time focused on information retrieval, supported by competency frameworks, with a strong emphasis on information evaluation. Cross-checking information, reflection on its quality and relevance remain central; but when emotions, desires, beliefs come into play, new needs are emerging, pointing towards critical analyses and strategies, less dependent on media frameworks and representations (Kellner and Share, 2007), not limited to thinking techniques, but questioning preconceptions, stereotypes, relation to texts, with attention to the regimes of truth, taking into account the contexts. Information-documentation, as a field of practices, is not a discipline in France. But recent official documents (collège since 2016; lycée, 2019) introduced “Information and Media Education” (IME) in disciplinary programs, in a formal but fragmented way. Regarded as a necessity in the post-attack context, it is included in the "Citizen Pathway" in support of Moral and Civic Teaching (EMC), then designed to enable students to develop citizen media practices. It appears also in the new subject "Digital Sciences and Technologies", created in 2019 (lycée, Seconde) which encourages a thoughtful and reasoned use of digital technologies. How do teacher librarians and teachers deal with Information and Media Education in this context? This paper explores what does it means, in a so-called post-truth world, to be critically educated about information, documents, media, essential to be an informed citizen? To answer these questions, we rely on an ongoing research (part 2, qualitative) in French secondary education (collèges, lycées), whose objective is to study current changes in the field of Information and Media Education in today's digital world. For this paper, particular attention is paid to info-documentary training sessions, observed over time in a few selected schools, with a comprehensive approach. To this end, observations are discussed in terms of constructive pluralism, according to an a posteriori methodology, in which the researcher is in an inquiry process, attentive to the meaning of emerging dynamics. After presenting the context of the study, and defining the concepts of fake news and critical (information) education, we will question the potential and the limits of these training sessions.