Fraction Multiplier
Simon Gregg had the idea to use the fraction modeler to show multiplication. For students to draw, I prefer rectangles because they're easier to draw, but students do gravitate to fraction models, so maybe this can be supportive.
Circle Model Fraction comparison:
http://geogebratube.org/student/m694587
A Rectangle Model multiplication:
http://geogebratube.org/student/m132103
More GeoGebra at bit.ly/mh-ggb