Over the past three decades, digital gaming has become an increasingly significant part of children’s culture. While this development has attracted significant academic attention, much less attention has been given to the technological dimensions of the games themselves. As critical theories of technology demonstrate, however, technological artifacts are far from “neutral.” Rather, technologies embody and at times reproduce the social, economic and political conditions within which they are constructed. Through the inclusion of certain technological affordances (and not others), design decisions, industry norms, legal/regulatory requirements, and programmed game rules, this thesis argues that corporate priorities and dominant discourses about children’s digital play become embedded within the very technical code of digital games. Focusing on game-themed virtual worlds, or massively multiplayer online games (MMOGs), this thesis uncovers the political and social dimensions of children’s MMOGs, and identifies the conditions these new game systems introduce into children’s play. Drawing on a multidisciplinary theoretical framework, the research methodology follows a two-level approach to children’s MMOGs as sites of struggle, in which children are in constant negotiation with the games’ formal and informal “rule systems,” which include industry trends, design choices, game rules, and government policy. A general overview of the children’s multiplayer online game environment is provided, and major trends are identified. In-depth analysis of six case studies is provided, which include Nicktropolis, BarbieGirls, Toontown and Club Penguin, Magi-Nation and GalaXseeds.Through design analysis, political economic analysis, and in-game observations, this examination reveals how systems of regulation, social assumptions and power relations are reflected within the rule systems contained within the design, management and configuration of the games and their players. The findings reveal that the games’ designs are much more restrictive than what is allowed by MMOG technologies, and that these games have adopted a rigid rule system aimed at aligning children’s play with commercial interests.