Scientific literacy is still being identified and recognised as one of the main goals of science education. However, this concept has multiple interpretations and its definition changes continuously depending on its social, cultural, and political contexts. In this paper, scientific literacy is conceptualised through "visions I, II and III." The first one is focused on the content and scientific processes for its subsequent application; the second, with a focus on understanding the usefulness of scientific knowledge in life and society; and the third one seeks to move towards a politicised scientific education to dialogic emancipation, attending social and eco-justice dimensions. The latter is also called critical scientific literacy. The research aimed at analysing how scientific literacy and these three visions are expressed in school curricula of Bolivia and Chile. Using a qualitative approach and thematic analysis, it is established that the Bolivian curriculum presents mainly a "critical scientific literacy" approach and the Chilean science curriculum presents mainly a "vision II" of scientific literacy. Findings of contrasting both school curricula show science education as non-neutral and profoundly political field, and therefore, we can see relevant opportunities for transformation and emancipation, understanding science curriculum as a social practice.