You'll need a few of these globes (or one globe plus some cheap beach balls). Before beginning your study of Geography or Earth Science, have your kids study the difference in size between Greenland and South America. Then, challenge your kids to cut this round ball apart and glue to a poster board in such a way that you make a flat map. It's impossible to make the round Earth into a flat map without a lot of gaps in the process! Now have them look at a flat wall map of the world and compare the size of Greenland and South America. Can they figure out why Greenland and S America are practically the same size on the wall map when the globe shows that Greenland is much smaller?