Welcome to ! The GISMO research team at North Carolina State University has developed 18 learning trajectories that unpack the K-8 Common Core State Standards for Mathematics from the standpoint of student learning, and elaborate the underlying scientific research in mathematics education. The hexagon map illustrates these learning trajectories, standard by standard. Clicking on a hexagon or a trajectory takes you to detailed descriptors that articulate students' progression from prior knowledge and naïve conceptions to more sophisticated mathematical concepts and reasoning. TurnOnCCMath is a comprehensive resource to support teachers, teacher educators, professional development providers, and district and state-level curriculum experts in interpreting the CCSS-M for instructional implementation. Documented throughout with citations from research and practitioner journals, TurnOnCCMath will also support educational researchers in identifying fruitful areas for further research on student learning.