Broadcasting children's music on television and radio is motivated by, and aims to serve, adults' perceptions of children's wants and needs. Children's music in general is shaped by the understanding of what 'childhood' means and, in turn, supports adults' assumptions about childhood.This article develops these ideas in an analysis of examples from the history of British radio and television, beginning in the 1920s and continuing until the growing penetration of online interactive media challenged the status of broadcasting in the early 21 st century. The article discusses examples of different kinds of children's music in a broadcast context, including the broadcast of commercial recordings of music for children, such as versions of traditional songs and nursery rhymes as well as pop music aimed at children. It also considers the significance of signature tunes and repeated musical sequences from long-lived and well-loved children's programmes, because they play key roles in differentiating children's programmes from each other and distinguishing children's music from music aimed at adults. Broadcast programmes frequently include music that does not play a central role, when it is used as an accompaniment to drama, entertainment performance or animation. But such music contributes to programmes' tone and shapes their mode of address to an imagined child audience.Entertainment shows or magazine programmes include music performances alongside non-musical sequences and can use music to, for example, mark an occasion for sing-along activities or accompany games. The social function of broadcasting for children watching or listening at home or at school, usually with an adult or other children, is constituted in part by these varied forms of children's music.These forms of music shape conceptions of childhood through particular kinds of listening practices and ways of belonging to an audience.