Did you know that approximately 70 percent of Earth's surface is covered in water? And yet, less than one-tenth of one percent of all that water is drinkable. In fact, if you were to fill a gallon jug of water, and thought of that gallon as being all the world's water, less than one teaspoon of that water would be drinkable. Water is a precious commodity in our world, and it also provides a great starting place for seeing some amazing science take place.