The study of small group idiocultures offers a productive way to study the role of culture in human cognitive and social development. My evidence is drawn from a multi-decade long study of groups of mixed-aged participants engaged in deliberately designed forms of joint activity taking place several times a week over periods extending over decades in a variety of institutional settings. In each such system, participants ranging from middle childhood to adulthood participate in an after-school program composed of a wide variety of games brought together in a fantasy world watched over by a Wizard. Insights offered by this approach include comparative analysis of skill development in different idiocultural systems, intergenerational changes in the local cultural systems themselves, and intra-cultural variations in the behavioral changes of individual children occurring over different time scales. Implications of this comparative approach for psychology science are discussed.
Keywords: child; culture; development; diversity.