This dissertation investigates the use of podcasts in high school classes of German as a Foreign Language (GFL), in levels B2 and C1 of the Common European Framework of References for Languages. This technology provides for quick and free access to authentic audio or video materials taken from German radio and TV programs, so that teachers have a wider range of resources for their classes and students have contact with the language which was produced for purposes other than pedagogical ones. Considering the proposals in the Parâmetros Curriculares Nacionais para o Ensino Médio (National High School Curricular Parameters), the levels of reference of the Common European Framework of References for Languages, and the goals set in the Rahmenplan Deutsch als Fremdsprache für das Auslandsschulwesen (Framework German as a Foreign Language for schools abroad), this study discusses the potential and the limitations of the use of this technology as a tool for teaching and learning GFL in a bilingual school. Based on the principles of Activity Theory, this work aims to investigate how the implementation of podcasts affects the activity system of GFL classes from the teachers’ and students’ perspectives in a bilingual school in Rio de Janeiro.