This classroom-based study, which took place in a French Polynesian primary school context, attempts to highlight the role played by social artefacts on the quality of dialogic exchanges and mediation of learning in beginner level young foreign language learners in Content and Language Integrated Learning (CLIL) classes. The CLIL experience described in this study is based on a sociocultural framework and the principles of the Action-Oriented approach (AOA). The study employed classroom observations and video recordings to gather data, which were then analysed qualitatively using discourse analysis. The discourse was split into meaningful segments and studied by focusing on the role social artefacts and gestures played during dialogic exchanges. The analysed data indicated that socially-mediated activity designs which enable the use of artefacts and gestures facilitate the mediation of learning, extend dialogic exchanges and improve the communicative quality of classroom interactions.