Didactics-Driven Development: Towards a Methodology and Toolset for the Systematic Validation of Applied Games is an applied research project addresses the problem of validation of Applied Games, in particular Serious Games with specific didactic goals and intended outcomes. The project aims at establishing a methodology and a tool for the systematic validation of such applied educational games. The methodology is inspired by Test-Driven Development, adapted for educational games, by supporting dynamic requirements relating to didactic goals and intended outcomes, and tracking design decisions related to these didactic concerns. The tool will support making explicit these didactic concerns, and monitoring and measuring the actual educational outcomes, during the development process.