I got a nice comment on a blog post form Pamela Rawson and I ended up reading her neat post talking about her new 3D geometry class:

https://rawsonmath.wordpress.com/2016/01/26/how-do-we-know-that/

The point of the Week 3 MTBoS Blogging initiative isn’t the course specifics, I know, but still the idea of a 12 week course focusing on 3D geometry captured my imagination.ย I never studied 3d geometry in any formal way, but exploring that subject with my kids has been incredibly fun.

For example:

and more recently this tweet from Simon Gregg (and the animated gif inside of his blog post) inspired a super fun project:

My work prepping to explore folding a dodecahedron into a cube with the boys is here:

and the project with them is here:

Can you believe that a dodecahedron folds into a cube!

Moving away from our Zometool-related projects, we’ve done a few fun 3d geometry projects using just snap cubes. For example, this tweet from Five Triangles made for a neat project:

A neat counting problem shared by Five Triangles

This project explored the connection between the sum of squares – and geometry:

and it was realted to another 3D geometry project inspired by a tweet from James Key:

A neat geometry project inspired by a James Tanton / James Key tweet

I could go on and on and on and on, but I’ll just stop at one more fun one – the volume of a sphere:

The Volume of a Sphere via Archimedes

All of our 3D geometry projects have the “3D Geometry” tag on the blog, that list of projects is here:

It is such a fun subject!!