In higher education the teaching of physical quantities and units of measurement is traditionally arranged as a preliminary technical section aimed at memorizing the base and derived units of the International System and at drilling the conversion of multiple and submultiple values. Meanwhile the competencies of natural science literacy – the scientific explanation of phenomena, the evaluation and planning of scientific inquiry, the interpretation of data and evidence – unfold precisely through operating with quantities, their dimension, order of magnitude and uncertainty. The discrepancy between the procedural treatment of the topic and the activity-based nature of literacy forms a methodological problem that has not received a consistent solution. The aim is to construct a model that maps the didactic elements of the topic onto the competencies of natural science literacy of students. Conceptual-categorial and structural-functional analysis, content analysis of the current educational and metrological regulatory documents, comparison of methodological approaches and modelling are applied. The content of the topic is decomposed into didactic elements, and their attachment to particular competencies is established; a typology of learning tasks and a level-based characterization of the ability to operate with quantities are proposed. The mapping shows that quantities and units form the operational language in which all three competencies of literacy are deployed, while the redefinition of the units of the International System through fundamental constants gives the topic a contemporary content that itself models the idea of invariance and measurement accuracy. It follows that the formation of literacy is achieved by shifting the emphasis from the procedural conversion of units to contextual and estimative work with quantities within the already existing section of the course.