This article describes the two types of reasoning in fraction conceptions that students often use, "gap" and "missing piece," and one that the authors aspire their students to reach, "residual." Each of these types of reasoning are underpinned by a different conception of fractions. Students who use "gap…

Understanding negative numbers can be challenging for many students, as these concepts may seem less tangible than counting objects, which are commonly represented by positive numbers. In addition, the multiplication of two negative numbers resulting in a positive might appear inconsistent and puzzling to young learners who are used to seeing the…

In this article, the author describes strategies to support students in conjecturing in ways that promote their agency. Conjecturing involves justifying (i.e., a practice that promotes epistemic agency and engages students in mathematical reasoning to defend their claims; Bieda & Staples, 2020) by which a conjecture becomes proven, modified,…

Emphasis in teaching and learning statistics has shifted from memorizing formulas and procedures to investigating situations, creating models, and using data to understand problems. The Common Core State Standards for Mathematics (CCSSM) (NGA Center and CCSSO 2010) Grade 8 Statistics and Probability content standards drive this point home.…

Teachers are constantly looking for new ways to make mathematical procedures such as radical simplification meaningful for students. In classes, teachers discovered what researchers have long known, that students who only memorize a set of steps get confused when their steps do not match a new problem or scenario perfectly. The area and side…

This article describes a modeling project the author did with his algebra, geometry, and applications students in grades 9, 10, and 11 as an enrichment and exploration of an extremely relevant real-world phenomenon and introduction to the adult profession of epidemiologist. With discussion and exploration, this project consumed two periods of 88…

Facilitating meaningful discourse directly supports what students should be able to do with respect to the third of the eight Standards for Mathematical Practice (SMP 3) in the Common Core State Standards for Mathematics (NGA Center and CCSSO 2010): "Construct viable arguments and critique the reasoning of others" (p. 6). Following best…

Two of the Standards for Mathematical Practice (SMP) in the Common Core State Standards for Mathematics (CCSSM; NGA Center and CCSSO 2010), "Look for and use structure" (SMP 7) and "Look for and express regularity in repeated reasoning" (SMP 8), are particularly abstract and sometimes clear only in the mind. For a given…

Natural disasters often receive massive media attention. The headlines can engage students to think mathematically and scientifically about the world around them. 'Principles and Standards for School Mathematics' explicitly encourages instruction where students "recognize and apply mathematics in contexts outside of mathematics" (NCTM…