This article shares an activity scaffolding the construction of the circumcenter of a triangle, culminating with a Triangle-Ball Championship game.

# Browse

## Construct It! Progressively Precise: Three Levels of Geometric Constructions

### Carmen Petrick Smith

## The Do Nothing Machine

### Keith Dreiling

The Trammel of Archimedes traces an ellipse as the machine’s lever is rotated. Specific measurements of the machine are used to compare the machine’s actions on GeoGebra with the graph of the ellipse and an ellipse formed by the string method.

## Algebraic Thinking in the Context of Spatial Visualization

### Arsalan Wares and David Custer

This pattern-related problem, appropriate for high school students, involves spatial visualization, promotes geometric and algebraic thinking, and relies on a no-cost computer software program.

## Math-Inspired Artwork

### Alessandra King, Sophia Ouanes, and Claire Doh

Students and teachers enjoy exploring the boundaries between mathematics and art.

## The Hidden Beauty of Complex Numbers

### Juan Carlos Ponce Campuzano

## The Case for High School Math Pathways

### Eric Milou and Steve Leinwand

The standard high school math curriculum is *not* meeting the needs of the majority of high school students and that serious consideration of rigorous alternatives is a solution whose time has come.

## Perspectives from Physics: Constraints on Our Curriculum

### Victor Mateas

How trigonometry is used and portrayed differently in mathematics and physics textbooks highlights potential sources for student struggle, constraints on our trigonometry curriculum, and lessons learned when looking across STEM disciplines.

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S^{3}D: Small-Group, Student-to-Student Discourse

### Sarah Quebec Fuentes

Learn about strategies and tools to examine and improve your practice with respect to fostering equitable small-group, student-to-student discourse.

## Exploring Geometry with Origami One-Cut-Heart

### Lauren R. Holden, Yi-Yin (Winnie) Ko, Devon W. Maxwell, Connor A. Goodwin, Cheng-Hsien Lee, Jennifer E. Runge, and Elizabeth B. Beeman

One-Straight-Cut-Heart activities can help teachers support students’ engagement with geometry and can deepen students’ geometric reasoning.

## A Radian Angle Measure and Light Reflection Activity

### Hanan Alyami

During a Desmos activity, students adjust the measures of angles in radians to reposition a laser and a mirror so the beam passes through three stationary targets. The Radian Lasers activity can be extended to simulate project-based learning.