Fawn Nguyen recently published an incredible blog post about a project related to the Euclidean Algorithm that she did with her students:
Fawn Nguyen’s “Euclid’s Algorithm
 The above link is broken, but Fawn’s post is here:
Fawn’s projects are usually very easy to do right out of the box, and this one is especially easy since you can just start with her pictures. So, we just dove in.
You’ll see from the comments my kids had that Fawn really has made using this blog post effortless:
Next I asked them to make their own shapes. They built the shapes off camera and then we talked about them.
At the end I asked them when they thought a shape would require 1x1x1 cubes.
After hearing their thoughts about relatively prime numbers at the end of the last video I asked them to make a shape that wouldn’t require 1x1x1 cubes to finish. Here’s what they made and why they thought it would work:
Such a fun project. Fawn’s work is so amazing. I love using her posts with my kids.