Shepard's Software has a collection of free Educational Web Games. Of interest is the Asian Geography collection of games. You can earn the geography of Asia with these ten games. Features include speech, interactive maps, blurbs, and links for each country to get more information
Vexillology is the scientific study of flags and related emblems. There is a collection of pages called "Flags of the World." There the one on "Cambodian Flag History." Here you will find images of the Cambodian flag and historical information about how the flag has changed. I used the site as a resource to develop my Cambodian Flag Arts & Craft project.