Teaching students how to construct cartogram maps will help them compare countries' populations, land areas, GNP, etc. It's a visual and mathematical activity that always gets the kids involved with comparing demographics and statistics of countries. I used this activity for many years with students for various geography projects, but originally found the idea from this award-winning lesson plan: (click on image to enlarge)
I found several other links and websites using online tools to build cartograms as well:
WorldMapper...Amazing pre-made World (MANY TOPICS!!) Cartograms
HOTCHALK: Exploring the USA and and the World with Cartograms:
RETANET: Cartograms to learn about Latin America
