Bullying is a pressing issue that challenges educational and other social practitioners, as many students' schooling process is impeded, often significantly, as regards safety and physical and psychological health. This issue, which is widely discussed in the public sphere and is often debated by adults, also concerns youngsters. Here and elsewhere, measures have been implemented to reduce and prevent bullying in schools. How do high school students interpret the phenomenon of bullying when they are invited to discuss it among themselves in focus groups? What do they say and how do they talk about it? Through the theoretical framework of symbolic interactionism this article sheds light on the meanings that high school students attribute to bullying and on the emerging interactive dynamics that emerged during their discussions. The analysis of the discursive segments manifested a co-construction of meanings stimulated by the interactions students engaged in, and fed by different sources of knowledge that revealed, in a broader sense, students’ relationship to knowledge. In conclusion, we stress the important role of adults for mediating interactions that support the transformation of students’ cognitive capacities and enable them to understand the complexity of the problems with which they must deal.