# Browse

### Heather Lynn Johnson, Peter Hornbein, and Sumbal Azeem

A computer activity helps students make sense of relationships between quantities.

A set of problems of many types

### Arsalan Wares

A paper-folding problem is easy to understand and model, yet its solution involves rich mathematical thinking in the areas of geometry and algebra.

A set of problems of many types

### Kien H. Lim

Meaningful context motivates students to appreciate the usefulness of variables, expressions, equations, and symbolic transformations.

A set of problems of many types

A set of problems of many types

### Debra K. Borkovitz

A few years ago, I encountered two different problems in which the number 3 played surprising roles. I found myself wondering, “Why 3? What's so special about 3?” Further investigation led to continuous extensions involving exponents, logarithms, a parametric equation, maxmin problems, and some history of mathematics. As you read, pause to try the problems and play with the applets (the article's title is a big hint!)