Integrating traditional learning content with the feeling of enjoyment that has made commercial video games wildly popular presents a significant design challenge. Serious video games, or games for learning, are most often studied from the viewpoint of disciplines such as psychology or education. There is a lack of applied research to guide serious game design, particularly the development process. Such frameworks are nonexistent or in their infancy. This thesis extends game design theory and creates an applied design framework for serious game development. It focuses on gameplay - the connection between the interactive engagements happening on-screen and the methods by which those events are manifest. Two game design constructs are conceptualized, linked, and illustrated: player archetypes and gameplay themes. The design framework is an applied tool to help serious game designers make video games that are both fun and educational, and that maximize audience appeal. The framework has broad design utility and is suited for use across a spectrum of serious game genres and content areas. The framework is illustrated with examples based on a University of British Columbia serious game project that is the focus of a community-based participatory research project with the municipality of Delta, British Columbia. The game, Future Delta 2, represents a new way to engage hard-to-reach community groups like youth in building awareness and action around the local causes and impacts of climate change.