GeoGebra Global Gathering  

Area of a Circle, by Anthony Or, Hong Kong  

Article by Anthony Or about how he created the Area of a Circle GeoGebra applet  

Best fit curve: sum of first n natural numbers  

Combinatorial approach: sum of first n natural numbers  

Geometric approach: sum of squares of first n natural numbers  

Dynamic proof: sum of squares of first n natural numbers, by Irina Boyadzhiev  

Scripting tutorial (very basic)  

Example (ideas from basic scripting tutorial): basic fractions practice (elementary)  

HIGHLY RECOMMENDED Sierpinski Arrowhead tutorial without words, from GeoGebra Türkiye  

GeoGebra Tutorial 3: Advanced Slider Uses, by Andrew Martin (Dan Meyer's taco cart example at the end)