This article, drawing upon fieldwork from a larger project investigating the nature of children's self-chosen musical play, explores instances of play that stumble and either morph into something else or are abandoned altogether. Four vignettes of musical play are described, documented during recess observations at several Canadian elementary school playgrounds. Each of the play episodes is analyzed in terms of how the play malfunctions musically and socially, from an adult observer's viewpoint. Self-determination theory is employed as a tool for analyzing these apparent gaps in proficiencies. Recognizing children as agentive and creative social actors, the author argues for the importance of protecting their free play time at school, where they are uniquely able to practice communicative (including musical) and social skills within a complex and constantly changing social setting. The separation of younger and older children on the playground is identified as one impediment to the apprenticeship learning system through which playground games have long been "caught". From the examination of instances of "unsuccessful" musical play the author suggests implications for elementary music education pedagogy.