This symposium aims to expose some of the social dynamics of theory development in the learning sciences by examining one particular case. It examines how individual studies contribute to theory development by using and extending an original theory of conceptual development, coordination class theory. We show how the diversity of contexts in which these ideas have been applied has contributed, not so much to validation, but to genuine expansion of meaning and power of the theory. This pattern emphasizes the essentially social nature of theory construction, and also a striking parallel between theory development in professional science and ideas about conceptual development in students that emphasize the role of multiple contexts. We discuss theoretical and methodological issues of communal development of a theory, such as theoretical power, fit, extension and generality.