Zeroing in on Number and Operations, Grades 3-4 provides thirty research-based, classroom-tested modules that focus on the key mathematical strategies and concepts essential for these elementary grades--whole numbers, addition, and subtraction; multiplication and division; and fractions and decimals--while highlighting the importance of teacher language in the development of those skills. The flipchart format makes it easy to access the key resources: summaries that identify the mathematical focus and associated challenges and misconceptions; instructional strategies and activities that develop conceptual understanding and computation skills; activities and ideas for adjusting the activities to meet individual needs; reproducibles for instructional use; and resources for further reading.