The focus of the project is the integration of computer science and mathematics concepts in a middle school course. The project's goal is to explain students' learning of four concepts that are part of both mathematics and computer science: variables, expressions, loops and abstraction. The project will design a middle school computer science course to incorporate the mathematics concepts. It will explore technology-based dynamic representations that are part of an interactive computer-based system. The research results and product development are potentially transformative to mathematics, science, and computer science teaching and learning in light of the expansion of computer science courses nationwide and current national mathematics and science standards. The project has strong potential for impact because it focuses on signature concepts from mathematics and computational thinking that are both areas of overlap and foundational concepts across a range of grade levels and courses.