This article provides a model of online professional development that is consistent with recommendations from the fields of teacher education, technology staff development and online learning. A graduate mathematics education course designed and implemented using the model is presented to exemplify the model's core components and interactions. The model has been used to develop courses in using the World Wide Web to enhance the teaching of children's literature, mathematics, science, social studies, multicultural education, parental involvement, literacy, inquiry-based learning and English as a second language. The model's components and pedagogical foundations are applicable for the design and implementation of online courses in other disciplines with field-based learning experiences. Unique features of the model are also shared as well as findings from a formative evaluation study. (Contains 1 figure.)