Charles Xie is the Principal Investigator of six NSF-funded projects totaling over $7,000,000 (since 2008). His current research includes computational science, big data, learning analytics, educational research, performance assessment, cognitive science, learning sciences, computer-aided design, mixed reality, natural user interface, sensor fusion, and infrared imaging. He has developed Energy2D, Molecular Workbench, and Quantum Workbench and co-developed Energy3D. These software products have been used by numerous students. More recently, he is spearheading computational process analytics for educational research and assessment on scientific inquiry and engineering design. He is also the inventor of the Frame, a technology that integrates sensors and simulations to create mixed reality and natural user interface applications. He has authored more than ten peer-reviewed journal papers on STEM education research since 2006.