This chapter reports on a DLC classroom intervention involving upper secondary students in the trilingual province of South Tyrol. Students with different linguistic profiles reflect and comment on their multilingual resources and on the role that their core and/or more peripheral languages play in their everyday lives. The main aim of the intervention is to awaken students to their rich multilingual and cultural repertoires and to get them to see their multilinguality as an asset and affordance for further language(s) learning. A second aim of the project is to examine if and/or how macro-level ideologies affect adolescent learners’ conception of themselves as multilinguals. The students in the present action study are aged 15 to 17 years. All (apart from two) have been schooled within the German education system which, it is fair to say, carries a decidedly monolingual imprint along with a German-first policy. Multilingualism is welcomed in its idealised manifestation of balanced and near-native speaker attainment, but it is framed as problematic and potentially detrimental to students’ linguistic and academic attainment if it involves partial competences and/or less prestigious migrant or heritage languages. Preliminary findings are presented and discussed from a DLC perspective weaving together psycho- and sociolinguistic considerations as proposed in the recent literature.