This activity involves finding the distance between two points in a coordinate plane and emphasizes reasoning from repeated calculations, which is one of the mathematical practices specified by the Common Core State Standards for Mathematics.
Mathematical Explorations: Find the Distance: No Formula Necessary
Ryota Matsuura and Yu Yan Xu
If Only Clairaut Had Dynamic Geometry Tools
Hyewon Chang and Barbara J. Reys
Using Clairaut's historic-dynamic approach and dynamic geometry tools in middle school can develop students' conceptual understanding before they encounter formal proof in geometry.
Using Tiered Explorations to Promote Reasoning
Cory A. Bennett
Address the needs of diverse learners with a class structure that is designed around a crime scene theme and based on student choice and perceptions of the math being studied.
Informing Practice: Examples as Tools for Constructing Justifications
research matters for teachers
Kristen N. Bieda and Jerilynn Lepak
Research explores how to help students build from, instead of building with, examples when justifying mathematical ideas.
Math for Real: Packaging Golf Balls
“when will I ever use this?”
A package of three golf balls provides the real-world scenario for this ratio and area activity.