# Search Results

### Doug Wilcock

Students analyze a photograph to solve mathematical questions related to the images captured in the photograph. This month, two differently shaped soda containers are compared. Volumes, including volumes of revolution, are computed.

### Gloriana González and Anna F. DeJarnette

An open-ended problem about a circle illustrates how problem-based instruction can enable students to develop reasoning and sense-making skills.

### Michael J. Bossé and Kwaku Adu-Gyamfi

A geometry course for teachers—easily adaptable to a high school geometry class—integrates technology, reasoning, communication, collaboration, reading, writing, and multiple representations.

### Zhonghong Jiang and George E. O'Brien

Using technology to explore the Three Altitudes of a Triangle problem, students devise many proofs for their conjectures.

### Wendy B. Sanchez

Educating students—for life, not for tests—implies incorporating open-ended questions in your teaching to develop higher-order thinking.

A set of problems of many types

### Irina Lyublinskaya and Dan Funsch

Symbolic geometry software, such as Geometry Expressions, can guide students as they develop strategies for proofs.

### Ryota Matsuura

This article presents a method for approximating π using similar triangles that was inspired by the author's work with middle school teachers. The method relies on a repeated application of a geometric construction that allows us to inscribe regular polygons inside a unit circle with arbitrarily large number of sides.

### Brooke Becker

This activity allows students to build their own understanding of what it means to develop a solid argument.