Vocabulary Words with Meanings:

Condensation – The physical change of state in which a gas or vapor is transformed into a liquid, as in the formation of water droplets when water vapor cools.

Evaporation – A physical change of state in which a liquid is transformed into a vapor or gas usually through the application of heat energy; the opposite of condensation.

Precipitation – Water falling in a liquid or solid state, from the atmosphere to earth (e.g., rain, snow)

Transpiration – The process by which water absorbed by plans (usually through the roots is evaporated into the atmosphere from the plant surface (principally from the leaves)

Water (H2O) - An odorless, tasteless, colorless liquid made up of a combination of two parts hydrogen and one part oxygen.  Water forms streams, lakes and seas, and is major constituent of all living matter. 

Water Cycle – the paths water takes through its various states – vapor, liquid, and solid, as it moves throughout Earth’s systems (oceans, atmospheres, ground water, streams, etc.) Also known as the hydrologic cycle.

Students will be able to:

• Understand how the water cycle works
• Understand the phases of water 
• Understand how living organisms need water to survive
• Demonstrate how water travels around the earth.
• Understand how water impacts humans
• Understand living systems need water
• Read nonfiction text and interpret the author’s meaning
• Write an original nonfiction piece with an environmental message on how humans need water for survival.

One 45-60 minute class period

Reading Books:          Drop Around the World

Spring Waters Gathering Places”

Student Pages:             Water Journey Map, Spring Waters, Gathering Places answer sheet

                                   Student Writing Assignment and Rubric      

Teacher Page:              Chart on How Water Moves

Materials:                    Station cubes (9)

                                    Station Pictures (9)

                                    Station Picture Holders (9)

                                    Leather laces (30)

                                    Beads for 30 participants(different colors for each station)

                                    Pencils (30)

                                    Whistle (1) 

 (Strategies: Active Engagement, Explicit Instruction)

W:     Teacher writes the formula for water H₂0 on the board and ask students what the formula represent?  Then ask students how does water move around?

E:        Students listen and and read along to book " A Drop of Water" and discuss where the water travels.  Students then participate in an activity whereby they become a water molecule traveling through the water system.;

R:        Students will reflect  and write a story based on their experiences of traveling as a drop of water.

E:        Students will share their information with others in the class.

T:       Instruction is differentiated by the use of oral reading, movement, writing and presesntation.ect.

O:       Learning experiences are organized by moving from teacher led activities to group activity and presentation

Background

Making Connections 

When children think of the water cycle, they often imagine a circle of water, flowing from a stream to an ocean, evaporating to the clouds, raining down on a mountaintop, and flowing back into a stream.  It is often confusing for students to try to imagine that the water they are drinking today may have been part of a dinosaur’s bath thousands of years ago.  Role-playing a water molecule helps students to conceptualize the water cycle as more than a predictable two-dimensional path.

 Introduction 

Water covers 71 percent of Earth.  It constitutes 50-70 percent of the weight of all plants and animals, including humans.  Water consists of two parts hydrogen to one part oxygen. It can exist in liquid, vapor, or solid (ice) forms. Its unique physical properties enable life to exist on Earth. 

While water does circulate from one phase to another in the water cycle, the paths it can take are variable.  The amount of water on the planet is finite and is constantly circulating through the atmosphere and falling back to earth. This constant movement and changing nature of our water resources is describe in a process called the hydrologic or water cycle. 

Heat energy directly influences the rate of motion of water molecules.  When the motion of the molecule increases because of an increase in heat energy; water will change from solid to liquid to gas.  With each change in state, physical movement from one location to another usually follows. Example: Glaciers melt to pools which overflow to streams, where water may evaporate into the atmosphere. 

Gravity further influences the ability of water to travel over, under, and above Earth’s surface.  Water as a solid, liquid or gas has mass and is subject to gravitational force.  Example: Snow on mountaintops melts and descends through watersheds to the oceans of the world.

In the coldest regions of Earth, water is stored for a long time as ice and hard packed snow. But even ice and snow are in motion; glaciers slowly melt as they move inch by inch, icebergs break away from glaciers and float in the ocean, slowly melting as they move toward the equator. 

The movement of water is greatly influenced by the contour of land and geographic features such as mountains, valleys, and hills.  A watershed is the area of land that guides water through small streams toward a major stream or river. Water’s movement in the watershed, in turn, may change the shape of the land by erosion and sedimentation. 

One of the most visible states in which water moves is the liquid form. Examples: 1) Water is seen flowing in streams and rivers and tumbling in ocean waves.  2)  Water falls to the earth as rain.  3)Although not easily seen, water also travels as a liquid underground, seeping and filtering through particles of soil and pores within rocks.

Although unseen, water’s most dramatic movements take place during its gaseous phase. Example: On a hot day, water evaporates from a puddle and goes into the atmosphere changing from a liquid to a gas or vapor. As a vapor, it can travel through the atmosphere over Earth’s surface.  In fact, water vapor surrounds us all the time.  Where it condenses and returns to Earth depends upon loss of heat energy, gravity, and the structure of Earth’s surface.

Condensation is when water vapor is cooled and turns from a vapor back to a liquid.  Condensation can be seen as dew on plants or water droplets on the outside of a glass of cold water. In clouds, water  molecules in their gaseous form collect on tiny dust particles and when cool, turn into droplets.  Eventually, the water droplets become too heavy and gravity pulls the water to earth.

Living organisms also help move water. Humans and other animals carry water within their bodies, transporting it from one location to another. Water is either directly consumed by animals or is removed from foods during digestion.  Water is excreted as a liquid or leaves as a gas, usually through respiration. When water is present on the skin of an animal (for example, as perspiration), evaporation may occur.

 The greatest movers of water among living organisms are plants.  The roots of plants absorb water.  Some of this water is used within the body of the plant, but most it travels up through the plant to the leaf surface. When water reaches the leaves, it is exposed to the air and the sun’s energy and is easily evaporated.  This process is called transpiration.

Procedure:

Warm Up

Before the activity, set up the nine stations around the room (soil, plant, river, clouds, ocean, lake, animal, ground water and glacier). Place a station marker in the metal stand and the color coordinated container of beads at each station. Set the appropriate activity cube at each station; the word stay on the cube indicates the station and the color of beads.

 Chart of colors - There is a metal stand for each of the nine station cards

Activity 

Part A

Before doing the actual activity, make sure the students have a firm grasp of the content.  The following questions posed to the students will allow for discussion and learning.

• Ask students what the phases of water are (solid, liquid or gas) and give an example (refer to the introduction).  
• Ask students if they can tell you how many parts hydrogen and how many parts oxygen water consist of (2 parts hydrogen to one part oxygen (H₂0). 
• Ask students if new water is formed on the earth? Or is the amount of water on the planet finite and constantly circulating? Could we be drinking water that the dinosaurs bathe in thousands of years ago? 
• Ask students when water will change from solid to liquid to gas (heat energy influences the rate of motion and when the motion of the molecule increases because of an increase in heat energy; water will change from solid to liquid to gas). 
• Give this example – glaciers (solid) melts to pools (liquid) which overflow to streams, where water may evaporate (gas) into the atmosphere.  Ask students for examples. 
• Ask students about condensation – give the example of droplets on the outside of a glass of cold water.  
• Ask students about  how living organisms help move water.
•  Ask students what the greatest mover of water is among living organisms.

Part B 

Give each student a copy of “Drop Around the World”. Read the book with them to further reinforce the concepts of the “water cycle” and phases of water. 

Part C 

Ask students to identify the different places water can go as it moves through and around the Earth.  Write their responses on the board.  Discuss the processes that move water to these different places based on the previous class work and the book read.

The Water Journey Activity: 

1. Tell students that they are going to become water molecules moving through the water cycle, and that they will create a bracelet and a map to keep track of their movement. 
2. Explain that students will be divided among the nine stations (lake, plant, soil, ocean, ground water, animal, river, glacier, cloud). To determine where students start, have each student choose a leather string.  At the end of each string is a bead; the color of that bead indicates the starting station (for examples, pink equals glacier).
3. Give each student a Water Journey Map and pencil.  Students will use this to record their journey through the water cycle.  (Make sure students have either a clip board or a book to write on.) Tell students to draw arrows to each station they move to.  Students should also record anytime they stay at a station.  They may do this with a symbol of their choosing, such as a star or a circle. 
4. Have students look around the room at the different stations and have them identify the different places water can go from their starting station in the water cycle.  Discuss the processes that cause the water to move.  Sometimes water will not go anywhere.  (See teacher sheet on how water moves between stations.)
5. Students should discuss the form in which water moves from one location to another.  Most of the movement from one station to another will take place when water is in its liquid form.  However, anytime water moves to the clouds, it is evaporating, and is in the form of water vapor.
6. Explain to the students that in this role playing, a role of the dice (cube) determines where water will go.  Have the students line up behind the station marker indicated by the color of the bead on their string.  Rules: Students’ role the die (cube) and go to the location indicated by the label facing up.  If they roll stay, they should move to the back of the line.  When students arrive at the next station, they get in line.  When they reach the front of the line, they roll the die (cube) and move to the next station (or proceed to the back of the line if they roll stay).
7. Students should keep track of their movements by taking one bead from the station and placing it on their string.  Students should take a bead for each turn, including stays.
8. Tell students that the cycle will begin with the sound of a whistle.  In order for students to go through enough of the stations ten to fifteen minutes should be allotted.
9. Recap – water journey map, symbol of their choosing if they must stay at a station and as they move collect and put their beads on the string.

Wrap Up

Have students use both their bracelets and their Water Journey Map to write a story about the places they traveled.  They should include a description of what processes were necessary for water to move to each location and the state water was in as it moved.  Discuss any cycling that took place (that is, if any students returned to the same station).

Have students share their writings. 

Provide students with a location (e.g., parking lot, stream, glacier , animal, plant, groundwater ) and have them identify ways water can move to and from that site.  Have them identify the states of the water.

TEACHER PAGE

“How Water Moves”

• Review students'answers to preliminary questions and clarify where needed in order to ensure students understand concepts before progressing to the activity.
• Provide feedback and guide student understanding during the  activity in order to help students understand the components of the water cycle, the phases of water and how water can move from place to place.
• Observe and provide feedback to students as they write their stories to ensure an understanding of how water molecules move from place to place.

Project WET, University of Montana

DEP www.dep.state.pa.us   water