Last updated: April 20, 2022

Math Skill: Number comparison (3-digit numbers) & Addition & subtraction (3-digit numbers)

Science Skill: Earth Water

Grade level: 3rd – 4th grades

Environmental Area: Water

Area level: National-scale

Purpose: Understand how much water is used for what purposes and develop awareness of water quality


Our country uses about 322 billion gallons of water every day to meet our demands. Most of the water we use is freshwater (87%), and the rest is saline-water (13%). Freshwater is either extracted from surface water (lakes, swamps, rivers, and snow on the top of the mountains) or pumped from underground. About 71% of freshwater consumed in our country comes from from surface water and the rest  is from groundwater (29%) (U.S. Geological Survey, 2018).

Where does the extracted water go?

The largest amount of our freshwater is used for electricity generation in our country. The second largest water is used for irrigation purposes. About 80% of water resources are used for either electricity generation or irrigation purposes.

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(Source:U.S. Geological Survey, 2018)

Ohio River and disrupted water cycle

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The purpose of this activity is to enhance students’ skills in addition and subtraction and reading graphs, while improvingtheir understanding of how our waterresourcesare used in our nation. This activity was created based on data obtained from the U.S. Geological Survey.

worksheet & answer key

Math Skill: Number comparison (3-digit numbers) & Addition & subtraction (3-digit numbers)

Using the figure which shows how much and for what purposes surface water and groundwater are used in our country, students are asked to compare 3 digit-numbers and add/subtract 3-digit numbers.

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