Do your students need more opportunities do develop number sense and reasoning? Are you looking to get your students energized and talking about mathematics? Have you wondered how practical, replicable, and engaging activities would complement your mathematics instruction? This guide answers the question "What could I do differently?" by taking cues from some of the most effective types of routines commonly used to engage students in reasoning while developing and reinforcing their number sense. This book offers 20 different routines, all of which include content examples, extensions, and variations for grades 6-8. It includes a year's worth of daily instructional material that you can use each class period to promote student reasoning and number sense. The routines in this book will help students: (1) Frequently revisit essential mathematical concepts; (2) Foster and shore up conceptual understanding; (3) Engage in mental mathematics, leading to efficiency and fluency; (4) Engage in mathematical discourse by constructing viable arguments and critiquing the reasoning of others; (5) Reason mathematically, which can improve performance on high-stakes assessments; and (6) Move learning beyond "correctness" by valuing mistakes and discourse to encourage a growth mindset. From trusted authors and experts John SanGiovanni and Eric Milou, this teacher-friendly resource will give you all the tools and tips you need to reinvent those critical first five or ten minutes of math class for the better!