This study considers children's informal musicking and online music teaching, learning, playing, and invention through an analysis of children's clapping games on YouTube. We examined a body of 184 games from 103 separate YouTube postings drawn from North America, Central and South America, Europe, Africa, Asia, Australia, and New Zealand. Selected videos were analyzed according to video characteristics, participant attributes, purpose, and teaching and learning aspects. The results of this investigation indicated that pairs of little girls aged 3 to 12 constituted a majority of the participants in these videos, with other participant subcategories including mixed gender, teen, adult, and intergenerational examples. Seventy-one percent of the videos depicted playing episodes, and 40% were intended for pedagogical purposes; however, several categories overlapped. As of June 1, 2016, nearly 50 million individuals had viewed these YouTube postings.