Challenge your learners to wrap graph paper around a ping pong ball to represent the latitude and longitude of the earth. It just can't be done! But it's a great introduction to latitude and longitude. It can be looked at in two-dimensional form like looking at a map. This can be related to the Cartesian coordinate plane. It can also be looked at in three-dimensional form like on a globe. A great hands-on activity to learn about latitude and longitude.