Our paper provides an empirically based perspective on the contribution of Conversation Analysis (CA) to our understanding of children's second language learning practices in a multilingual classroom setting. While exploring the interactional configuration of a French second language learning activity, we focus our analytic lens on how five children and their teacher rely on multilingual resources (French, German, Luxemburgish, and Portuguese) in order to initiate and to improve the re-voicing of a story in French. Through a moment-by-moment (CA) video based analysis we can show how co-constructing the second language learning object involves various embedded linguistic and interactional competencies. We will point out how the participants engage in the re-voicing activity through their mutual orientation to each other's language conduct. Effective second language learning becomes possible because the teacher's student-directed talk provides opportunities for the children to provide oral narratives in a jointly constituted multilingually shaped interaction. Moreover, by offering insights into the interactional features (turn-taking system), CA allows us to visualize how the children's second language learning practices are interrelated with the sequential structure of multilingual talk-in-interaction. Thus, in our case study we emphasize the fundamentally social nature of second language classroom talk.