How has NCTM leadership shaped the evolution of teaching and learning mathematics? What are your expectations for NCTM leadership?
Trena L. Wilkerson
Sophia Kovalevsky's story
Erin E. Baldinger, Matthew P. Campbell and Foster Graif
Students need opportunities to construct definitions in mathematics. We describe a sorting activity that can help students construct and refine definitions through discussion and argumentation. We include examples from our own work of planning and implementing this sorting activity to support constructing a definition of linear function.
Rebecca Vinsonhaler and Alison G. Lynch
This article focuses on students use and understanding of counterexamples and is part of a research project on the role of examples in proving. We share student interviews and offer suggestions for how teachers can support student reasoning and thinking and promote productive struggle by incorporating counterexamples into the classroom.
Gabriel Matney, Julia Porcella and Shannon Gladieux
This article shares the importance of giving K-12 students opportunities to develop spatial sense. We explain how we designed Quick Blocks as an activity to engage our students in both spatial reasoning and number sense. Several examples of students thinking are shared as well as a classroom dialogue.