Resumen: There are plenty of books, journals and online sites devoted to the relationship between mathematics and cinema, and its educational applications, whose interest is to explore the pertinence of the instruction processes that can be designed around this resource. Instead of watching a full production, mathematics teachers that include movies and TV series in their classroom sessions, usually show short fragments, so the first step should be to consider these fragments alone to identify the mathematical objects and the involved meanings and representations. For this purpose, we use some theoretical notions from the Onto- Semiotic Approach to research in mathematics education, applying them to three excerpts from a movie and to some typical tasks designed based on them. The analysis of the involved mathematical content allows to reflect about the epistemic suitability of the instruction process, in terms of how aligned they are with the institutional meanings. The results show that it is possible to achieve a high suitability level but, most importantly, that this kind of analysis promotes teacher reflection to design teaching and learning processes. Idioma: Inglés Año: 2018 Publicado en: International journal of innovation in science and mathematics education 26, 1 (2018), 16-26 ISSN: 2200-4270 Originalmente disponible en: Texto completo de la revista