The authors provide pre- and inservice K–6 mathematics teachers with a complete array of tools and strategies, chief among which is Response To Instruction, to help identify learners’ skill levels and target instruction to meet each learner’s needs. Foundational to this learner-centered approach are the guidelines presented in the Common Core State Standards and the principles and standards developed by the National Council of Teachers of Mathematics. Each chapter deals with a different mathematics topic—from place value to problem solving. The case study format and inclusion of student examples promote a sound understanding of learners’ varied cognitive, behavioral, and physical needs—essential knowledge for designing appropriate teaching strategies. Also included is a variety instructional activities that can easily be implemented in the classroom.