Author: Daniel Scher

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 your body. This structure repeats, with more...

What Is All the Fuss About Lines?

Yesterday, I led a webinar that demonstrated how Sketchpad and Web Sketchpad can be a powerful tools for exploring Common Core algebra topics. My examples included solving for unknowns with a pan balance, exploring the slopes of lines, maximizing the area of a fixed-perimeter rectangle, and graphing trigonometric functions. I touched only briefly on each example during the...

The Dog Leash Investigation

Today’s guest post is from Marta Venturini, a PhD student in Mathematics Education at Simon Fraser University under a “Cotutelle Agreement” with the University of Bologna, where she’s a PhD student in Mathematics. While looking for some tasks that would be suitable for Sketchpad,  I found the “dog leash” problem in a March 2007 Kangourou...

Learn to Multiply Like No Bunny’s Business

It started with an unassuming bunny that hopped along a number line. In 2011, our team at KCP Technologies released Sketchpad Explorer for the iPad, making it possible for teachers and students to interact with desktop Sketchpad models on their iPads. We were thrilled to bring the iPad’s multitouch technology to Sketchpad, but sensed that there...

Introducing the Dynamic Number Project

Four years ago, my colleague Scott Steketee and I began brainstorming new Sketchpad activities for a National Science Foundation grant called Dynamic Number. Our goal was to use Sketchpad to make ideas from number, operation, early algebra, and algebra come alive through interactive models that emphasized conceptual understanding. Scott and I had lots of help....

Revisiting a Childhood Addition Code with Sketchpad

As a fourth-grader in 1977, I had a love-hate relationship with my Addison-Wesley textbook. Its contents overflowed with arithmetic problems, but every so often an entertaining brainteaser appeared to break the monotony of drill practice. These puzzles were clearly marked: Each appeared in a box set aside from the main text and featured a bespectacled...

Creating Origami Whirlpool Designs with Sketchpad

Tomoko Fuse is a Japanese origami artist whose designs are highly geometric. A Google search for her origami models reveals a plethora of boxes and intricate three-dimensional structures, many of which are folded from multiple sheets of paper and then assembled together. As an avid origami folder, I’ve always admired Fuse’s work. But nothing prepared...

Sketchpad Reflection Puzzles

In a recent blog post, Karen Greenhaus describes how it’s possible to construct familiar corporate logos using Sketchpad. You might start with a rhombus, for example, and then reflect it twice to obtain the Mitsubishi logo. Karen’s post got me thinking about other creative uses of transformations with Sketchpad. In particular, Sketchpad 5 allows you to...

Exploring Conic Sections with Sketchpad

As a student, I didn’t place conic sections on my list of favorite high school topics. The standard textbook treatment of the ellipse, parabola, and hyperbola seemed uninspired. There were messy algebraic equations with multiple square roots. There was lots of terminology. Drawing a conic meant plotting several points on graph paper and connecting them with...

When Factoring Gets Personal

As an author of Sketchpad activities, I like to think that I can pose good problems for students to solve. But as I visit elementary classrooms and watch students use Sketchpad, I realize that a large part of the enjoyment they derive from using our software comes from creating their own problems and sharing them...