Category Archives: Math Software
Iteration in the Complex Plane
Simultaneous Equations in Elementary School? You Bet!
Algebra classes devote considerable time to equations in a single variable before solving multiple equations in two or more unknowns. But just because elementary-age students are not familiar with algebraic symbolism doesn't mean they can't solve simultaneous equations, too!
The mathematician and educator W. W. Sawyer makes a compelling argument … Continue Reading ››
Arranging Addends Puzzles
Arranging Addends is an interactive puzzle that I designed on a long bus ride through Alaska. The goal of the puzzle is to arrange the circles and the six numbers (1, 2, 4, 8, 16, and 32) so that three conditions are met simultaneously: The sum of the numbers in the green circle is 21, … Continue Reading ››
Discovering the Angle Sum and Difference Identities
In my Advanced Methods class at Penn’s Graduate School of Education, my students are working in groups to create shared lesson plans using an inquiry approach. For a number of reasons it can be challenging for these pre-service teachers to identify appropriate topics for student inquiry, but sometimes the brainstorming they do turns into something … Continue Reading ››
A Hidden Polygons Puzzle
Take a look at the two groups of shapes below. Both groups contain an equilateral triangle and a square. Now imagine that you showed students each group and asked them to identify the shapes. Do you think students would do equally well in naming the shapes in group A and group B?
Wait for a Date
Consider the following probability question:
Two friends arrange for a lunch date between 12:00 and 1:00. A week later, however, neither of them remembers the exact meeting time. As a result, each person arrives at a random time between 12:00 and 1:00 and waits exactly 10 minutes for the other person. When the 10 minutes have passed, … Continue Reading ››
A Pythagorean Tree Grows in Your Web Browser
A little over a year ago, the Museum of Mathematics opened in the heart of New York City. One of my favorite exhibits at the museum is the Human Tree. When you stand in front of the Human Tree screen and wave, your arms are replaced by images of … Continue Reading ››
Discovery by Dragging
A few days ago I led a webinar on the Common Core and Sketchpad for Sketchpad beginners, and I showed four Sketchpad activities aligned with both the Content Standards and the Standards for Mathematical Practice. I mixed it up a bit … Continue Reading ››
Aligning Objects in Sketchpad
I recently got a question from a question from a user about how to line up text objects. The question was both about lining up objects on a page, and about lining them up from one page to the next, so that when you switch pages things are in the same place on every page.
As … Continue Reading ››