This article describes how fortuitous mathematical moments should be noticed, encouraged, embraced, and capitalized upon.

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### José N. Contreras

### Enrique Ortiz

This article presents an example of discovering an idea through creative play. After some trial and error, I drew a wonderful image, which I later learned was a two-dimensional view of a four-dimensional shape called tesseract.

### The Math Learning Center Content Development Team and J. Michael Shaughnessy

Problems to Ponder provides 28 varying, classroom-ready mathematics problems that collectively span PK–12, arranged in the order of the grade level. Answers to the problems are available online. Individuals are encouraged to submit a problem or a collection of problems directly to mtlt@nctm.org. If published, the authors of problems will be acknowledged.

### Rick Anderson and Peter Wiles

Recognizing the complex nature of students’ geometric reasoning, we present guidelines and suggestions for implementing a Guess My Shape minilesson that focuses students’ attention on properties and attributes of geometric shapes.

### Min Wang, Candace Walkington, and Koshi Dhingra

An example of an after-school club activity gives educators some tools and suggestions to implement such an approach in their schools.

### Amanda K. Riske, Catherine E. Cullicott, Amanda Mohammad Mirzaei, Amanda Jansen, and James Middleton

We introduce the Into Math Graph tool, which students use to graph how “into" mathematics they are over time. Using this tool can help teachers foster conversations with students and design experiences that focus on engagement from the student’s perspective.

### Zachary Champagne

Providing students the autonomy and choice to learn when productive struggle becomes unproductive is a core teaching belief in the author’s classroom. This article tells the story of one student’s ability to know and express when his frustration was too great and how he chose to walk away from his work and return the next day.

### Enrique Ortiz

For the Love of Mathematics

Answers are available in the