Flags are a good topic to introduce in basics of GeoGebra and dynamic constructions. For most of the flags geometric details like ratio of length and height, angles, ... are fixed, sometimes ways of construction is explicated. The biggest website with all flags of the world and intersting informations about the origin of the flag can be found at http://www.crwflags.com/fotw/flags/index.html.
- dynamic constructions of flags, mostly done by Romanian students. Click into the picture for the dynamic versions!