This is where I will put GeoGebra files, and links to GeoGebra files. GeoGebra is free software with many components: geometry, 3D geometry, graphing, CAS, and spreadsheet. It is available for pretty much all platforms on computers and tablets.

We will not have time to install software during the workshop, and at any rate, you will not need to use it in the Hands-On Geometry workshop. 
(I will use it to illustrate some ideas.) If you want to use the files when you're back at home or at school, you can download the application here

Here are some of the figures I will be using:

Pythagorean Theorem (and from there, two more)

To explore some other things I've done with GeoGebra, go to my Applets Directory.