Rapid changes in computing, especially with advances in artificial intelligence, are reshaping the future needs of society and the demands on the STEM workforce. More than ever, computer science (CS) education is critical for all children. Many schools are looking for ways to introduce CS skills and thinking in the elementary grades. Whereas some initiatives have focused on coding as its own endeavor, not integrated with subjects like mathematics, science, or literacy, developers and researchers are increasingly exploring ways that programming and computational thinking (CT) can be integrated into core content. This project investigates the idea that providing teachers and students with resources to integrate CS/CT with mathematics can mutually benefit learning in both disciplines. Embedding programming into core mathematics instruction for grades 2-5 ensures that all children gain experience with CT and programming in developmentally appropriate ways. It can also increase access to critical mathematics content by providing an engaging approach to mathematics that offers different affordances than pencil-and-paper activities. This project will develop resources that strengthen teacher capacity, engage children in mathematics learning, and prepare them for STEM education pathways. Working with school district partners in four states across the eastern U.S., the project will impact over 100 teachers and 2100 children. An additional 192 teachers in comparison classrooms will be