Utah State University Extension
Students will use 10 liters (approximately 2.5 gallons) of water to represent all the water on the earth. They will be given the percentage for each water source in relation to the total amount, and asked to divide the 10 liters of water to demonstrate this.
Mesner, Nancy, "Stream Side Science Lesson Plan: Where’s the Water?" (2014). All Current Publications. Paper 1234.