This project is investigating the potential that the combination of mobile devices and cloud computing offers to engage middle school children in scientific exploration using the same simulations and other tools that scientists employ to decompose, visualize, and understand complex systems, e.g. the spread of infectious disease or the sourcing, production, and use of energy across the globe. Drawing on Learner-centered Design (LCD) guidelines and research on motivation and learning, the project team is developing the Participatory Simulations Software Factory (PSimSF) which would produce Participatory Simulations (PSims) for various science processes that run on a broad range of mobile devices. The investigators posit that personal participation in the simulation, where a broad range of visualizations are employed, increases student engagement - with greater time on task and real-time conversation amongst the students, which in turn increases student achievement. The intellectual merit of the project rests in its team's combination of expertise and experience in working with emergent technologies, cutting-edge science methodology, and inquiry-based learning. Moreover, in creating and testing a number of prototype PSims, the project is helping the larger educational community to understand better what is the potential for these new technologies to support active, project-based learning. Finally, the mobile learning environment with its multi-player, game-like interactions builds on the characteristics of today's digital natives. The broader impacts of the project lie in the freely distributed PSims that the project is creating along with grade-level appropriate curriculum materials. The project is also aiming to make the work scalable and sustainable, with a specific focus on potential commercialization.