"It's hard to draw on a grapefruit."

To illustrate the difficulties of translating the realities of a spherical world into a flat 2D map, Mapping the World by Heart suggests drawing a map on a grapefruit and then trying to peel the grapefruit in one big piece and laying it flat. Here are some photos of our experience trying out this lesson.

I think they managed to comprehend the basic concept - a sphere doesn't translate to a flat map.