This workbook is a companion to the "Community Math Night Facilitators' Toolkit. REL 2022-120" (ED615952), a comprehensive resource for elementary school educators to plan and implement a Community Math Night. A Community Math Night brings together educators, students, and their families to: (1) learn about, talk about, and have fun with math; (2) reinforce positive math mindsets; and (3) help family members participate in their child's learning. The Community Math Night program helps schools and communities create a shared understanding of math concepts and raise expectations for math knowledge and achievement, both of which promote children's success in school. The content and activities in the Community Math Night Facilitators' Toolkit are based on key research related to supporting student success in math Understanding the research foundations for the Community Math Night program can help educators feel confident about hosting a math night and implementing math night activities. A stronger understanding of the "why" behind the Community Math Night program can also help educators connect the math night activities to their own beliefs and practices, which in turn can strengthen their work with students and families beyond the event. This workbook is designed as a professional learning resource for educators and other school staff, though other stakeholders may engage as they have interest. The workbook pairs with Section 1--Learn of the toolkit and includes important research on four key topics that form the basis of the Community Math Night program: (1) The importance of learning math for future success; (2) Supporting equitable family engagement in math; (3) Building a growth mindset and positive math attitudes; and (4) Effective practices for math instruction in elementary school. The workbook describes the research base and then provides examples of how to apply the evidence in practice. The workbook also includes questions prompting users to reflect on related teaching practice and to use while planning and implementing a math night. For each topic the workbook also includes a curated list of additional resources for deeper study. [For Appendix B-H Templates and Tools and Appendix I Instructions, Prompts, and Handouts, see https://ies.ed.gov/ncee/edlabs/projects/project.asp?projectID=6685 for links.]