Future City Lab: New York's Water II

Lesson Two: Engineering Water Use

Grade Level: Grade levels: 2-4
Keywords: conservation, engineering, efficiency
Source: www.flickr.com/thetejon

Time Estimate: 60 minutes 

Connection to Future City Lab: Living with Nature: How can New York City enhance its natural environment and cope with climate change? 


Students will: 

  • Understand that small choices can add up when using natural resources 

  • See that engineering can be used to solve environmental problems 

  • Interpret a basic graph to support class discussion 


  • Worksheet 
  • Large container, like a disposable turkey roasting pan or a Tupperware tub 
  • Measuring cup for large amounts 
  • Two empty gallon jugs 
  • Graph of New York City water usage 


  • CCSS.ELA-LITERACY.SL.2.2: Recount or describe key ideas or details from a text read aloud or information presented orally or through other media. 
  • CCSS.ELA-LITERACY.SL.2.3: Ask and answer questions about what a speaker says in order to clarify comprehension, gather additional information, or deepen understanding of a topic or issue. 
  • CCSS.MATH.CONTENT.2.MD.D.10: Draw a picture graph and a bar graph (with single-unit scale) to represent a data set with up to four categories. Solve simple put-together, take-apart, and compare problems using information presented in a bar graph. 

Guiding Questions

  1. How can we conserve water? 

  2. How can engineering positively impact the environment? 


    In this lesson, students are asked to think about how they use water throughout the day and what steps they can take to conserve water. They’re offered a demonstration to show how water can be wasted through ordinary actions like washing hands and then introduced to how improved consumer items like low-flow toilets and shower heads can lower water use. Last, they are asked to look at a basic line graph and interpret it to see how these consumer items have impacted city water use overall. 

    Download the Student Worksheet

    Download the Graph of New York City Water Usage


  1. Introduction
  2. Explain to students that one of the ways people can keep water clean and safe is by not using too much: we can help the natural processes of the water cycle by making sure there’s enough to go around for everyone. 

  3. Activity: How do I use water throughout the day?
  4. Have students fill out the attached worksheet. Encourage them to think about how they use water doing everyday activities like washing, brushing their teeth, using the toilet, or cleaning their pet. 

    Ask students to think about how they could avoid wasting clean water and sending it down the drain. Introduce the idea of conservation. 

  5. Demonstration: How much water do we use when we wash our hands?
  6. Note: after running demonstrations below, don’t send water down the drain! 

    Ask students how much water they think they use when they wash their hands. Explain that today you’re going to compare the amount of water used if the water is turned off while they scrub versus the amount used if they leave it running. 

    Put the large container under the faucet and run a simple experiment: ask for a volunteer to wash their hands. Allow the water to run while the student scrubs their hands. Use some form of control to time it – sing a song (ABCs) or something similar. Once student is done, take water used and measure. Then run the same experiment but turn water off while scrubbing. How much water is used? What’s the difference and scale? 

    Optional: Depending on class size, you might want to have all the students have a turn. (You might be able to do this if you have class routines already in place that involve hand-washing.) If you can think of a way to contain all the water used during handwashing, it could be an effective visual demonstration about how small choices add up to larger amounts of waste (or opportunities for conservation!)  

  7. Discussion
  8. Water use education: Explain that people have figured out ways to get things we already use to use less water – we call this process engineering. Engineering is problem-solving to make things run better or more efficiently. We call these kinds of products “water-efficient.” 


    Toilets: Before 1994, toilets would use 3.5 gallons of water per flush. Afterward, toilets had to use 1.6 gallons of water per flush. How much less water is that? (Answer: 1.9 gallons, or about 2 gallons. Measure out this amount in gallon jugs to demonstrate it to students.) Newer models can save even more water. 

    Shower Heads: New shower heads can make water feel just as strong but not use as much water – in fact, they can save as many as 5 gallons of water per minute. Can we estimate how many gallons that would be in a usual shower? (Answer: lead students towards something like 10-15 minute shower. Then, using age-appropriate counting measures, count out in sets of five and add up total for something in the 50-75 gallon range. With 2 gallons already measured out per above, students should start to be able to understand a sense of scale.) 

  9. Data Analysis
    • Show students the graph of water usage in NYC (data taken from NYC Open Data: https://data.cityofnewyork.us/Environment/Water-Consumption-In-The-New-York-City/ia2d-e54m). Look at the axes and define terms. Ask: Is water use going up or going down? 

    • When do you see the line start to point downwards? Can we figure out around what year that happened? (Answer: Students should be able to come up with something around the year 1990.) 

    • If I told you that the city started to stop allowing the sale of high-flow showerheads around 1990, and then water-efficient toilets were required a few years later, does that agree with what the graph is telling us? What might that tell us about the value of engineering in addressing public issues? 

    • About how much water do we use per person per day now? Based on our experiments today, does that surprise you? 

  10. Conclusion
    • Conclude the session by pointing out all the water you’ve used. Can the students think of ways to re-use it to make it useful rather than sending it down the drain? Answers can be like watering plants, or using to wash chalkboards later in the day. 

    • Optional extension: if weather and space permit, you might try leaving the containers outside to see how long it takes for water to evaporate.  

Additional Resources 

New York City’s Water Demand Management Plan: http://www.nyc.gov/html/dep/pdf/conservation/water-demand-management-plan-single-page.pdf 

Water Footprint Calculator: https://www.watercalculator.org/intro/ 

Fieldtrips: This content is inspired by the Future City Lab gallery in the Museum’s flagship exhibition, New York at Its Core. If possible, consider bringing your students on a fieldtrip! Visit http://mcny.org/education/field-trips to find out more. 


This series of lesson plans for New York at Its Core was developed in conjunction with a focus group of New York City public school teachers: Joy Canning, Max Chomet, Vassili Frantzis, Jessica Lam, Patty Ng, and Patricia Schultz.

This project was made possible in part by the Institute of Museum and Library Services.

The views, findings, conclusions or recommendations expressed in these lessons do not necessarily represent those of the Institute of Museum and Library Services.