Students apply their understanding of the natural water cycle and the urban "stormwater" water cycle, as well as the processes involved in both cycles to hypothesize how the flow of water is affected by altering precipitation. Student groups consider different precipitation scenarios based on both intensity and duration. Once hypotheses and specific experimental steps are developed, students use both a natural water cycle model and an urban water cycle model to test their hypotheses. To conclude, students explain their results, tapping their knowledge of both cycles and the importance of using models to predict water flow in civil and environmental engineering designs. The natural water cycle model is made in advance by the teacher, using simple supplies; a minor adjustment to the model easily turns it into the urban water cycle model.

Through an overview of the components of the hydrologic cycle and the important roles they play in the design of engineered systems, students' awareness of the world's limited fresh water resources is heightened. The hydrologic cycle affects everyone and is the single most critical component to life on Earth. Students examine in detail the water cycle components and phase transitions, and then learn how water moves through the human-made urban environment. This urban "stormwater" water cycle is influenced by the pervasive existence of impervious surfaces that limit the amount of infiltration, resulting in high levels of stormwater runoff, limited groundwater replenishment and reduced groundwater flow. Students show their understanding of the process by writing a description of the path of a water droplet through the urban water cycle, from the droplet's point of view. The lesson lays the groundwork for rest of the unit, so students can begin to think about what they might do to modify the urban "stormwater" water cycle so that it functions more like the natural water cycle. A PowerPoint® presentation and handout are provided.

Students learn about the techniques engineers have developed for changing ocean water into drinking water, including thermal and membrane desalination. They begin by reviewing the components of the natural water cycle. They see how filters, evaporation and/or condensation can be components of engineering desalination processes. They learn how processes can be viewed as systems, with unique objects, inputs, components and outputs, and sketch their own system diagrams to describe their own desalination plant designs.

Just as there's too much carbon dioxide in the atmosphere, there's now too much in the oceans, too. What does that mean for the creatures who live there, as well as life on land? [2:30]

The lesson introduces students to the steps of the water cycle and rivers. They think about the effects of communities, sidewalks and roads on the natural flow of rainwater. Students also learn about the role of engineering in community planning and protecting our natural resources.

This article explains how the ice and snow of the polar regions fit in the global water cycle and includes links to professional development resources.

Measure relative humidity in the air using a simple device made of a temperature sensor, a plastic bottle, and some clay. Electronically plot the data you collect on graphs to analyze and learn from it. Experiment with different materials and different room temperatures in order to explore what affects humidity.

The meaning of vapor pressure is introduced. The distinction between evaporation and boiling is discussed and explained. The reason that liquids undergo vaporization is explained.

Create your own Olympic medal out of clay with the help of an adult. Watch as your design hardens over time as the water in the clay evaporates.

ZOOM cast members use a homemade solar still to mimic the water cycle, separating pure water from a saltwater mixture. [3:34]

Students act as chemical engineers and use LEGO® MINDSTORMS® NXT robotics to record temperatures and learn about the three states of matter. Properties of matter can be measured in various ways, including volume, mass, density and temperature. Students measure the temperature of water in its solid state (ice) as it is melted and then evaporated.

Using a household fan, cardboard box and paper towels, student teams design and build their own evaporative cooler prototype devices. They learn about the process that cools water during the evaporation of water. They make calculations to determine a room's cooling load, and thus determine the swamp cooler size. This activity adds to students' understanding of the behind-the-scenes mechanical devices that condition and move air within homes and buildings for human health and comfort.

Groundwater is one of the largest sources of drinking water, so environmental engineers need to understand groundwater flow in order to tap into this important resource. Environmental engineers also study groundwater to predict where pollution from the surface may end up. In this lesson, students will learn how water flows through the ground, what an aquifer is and what soil properties are used to predict groundwater flow.

Animation and text explain the water--or hydrologic--cycle, which is the process that water undergoes in nature.

Water is the source of life on earth. It exists in many forms and is constantly changing. The circulation and conservation of earth's water is called the hydrologic (or water) cycle. Find out how water evaporates, condensates, precipitates, transpires, and is transported around the earth.

This animation from NASA visualizes the steps of the water cycle, including precipitation, evaporation, transpiration, and condensation. [0:52]

Students use a thermal process approach to design, build and test a small-scale desalination plant that is capable of significantly removing the salt content from a saltwater solution. Students use a saltwater circuit to test the efficiency of their model desalination plant and learn how the water cycle is the basis for the thermal processes that drive their desalination plant.

Students learn about the water cycle and its key components. First, they learn about the concept of a watershed and why it is important in the context of engineering hydrology. Then they learn how we can use the theory of conservation of mass to estimate the amount of water that enters a watershed (precipitation, groundwater flowing in) and exits a watershed (evaporation, runoff, groundwater out). Finally, students learn about runoff and how we visualize runoff in the form of hydrographs.

Learn about the four phases of the water cycle, the ways in which watersheds are crucial to healthy water, and the best ways to manage local watersheds with this interactive lesson.