Images are omnipresent in the communicative practices of adolescents, and can be considered a «polyvalent object» (Féroc-Dumez, 2019) whose emotional and ethical dimensions are regularly highlighted as a key educational issue. I transpose a social semiotics method (Saemmer, Tréhondart and Coquelin, 2022) to the school context, encouraging ideological introspection and critical thinking when interpreting images. An experiment with middle-school students highlights the potential of social semiotics as a pedagogical tool, helping them to acquire both semiotic and reflexive tools. It transforms them into « involved interpreters », and allows at the same time exploring some of society’s most pressing issues, such as gender stereotypes and the use of digital platforms.