This paper analyses the cultural practices that were introduced in a radio improv class on the first day of Youth Radio Arts for immigrant students, and how these practices served as resources to mediate students' understanding of, and realisation of 'voice' over time. The theory-method combines insights from interactional ethnography and postmodern approaches to multilingual language ecologies. The analysis focuses on speech body play, parody, and embodied expression as salient dimensions of interactions with the radio improv mentor that found echoes in student reflections at the end of the year regarding the purpose of the programme and the meanings of voice and communication. The analysis of interactions from the first day together with ethnographic records from across the year, revealed the importance of taking into account the subjective and affective dimension of language, embodied perceptions, and cultural memory in multilingual settings constituted by transnational students.