Journey of a Raindrop

Transcription

1 Journey of a Raindrop Grade Level Second to Fourth Duration Prep time: 15 minutes Activity time: 30 to 60 minutes Materials 10 different colored pony beads (from craft stores) 10 large pieces of paper to designate stations ( See Teacher Tips) 10 cubes labeled according to water stations (See Teacher Tips) Clipboards Lined paper Pencils Worksheets Journey of a Raindrop Learner Objectives Students will: Identify at least 4 different ways in which water moves through the water cycle Write a story of a water molecule as it moves through the water cycle, using the beads that they create as a visual illustration of the water's journey Getting Ready! Read background information Arrange a space suitable for students to rotate between 10 stations Ensure that there are enough supplies for each student to have between 11 to 21 beads Summary The purpose of this activity is to explore the movement and state of water within the water cycle. Background Information While water circulates from one point or state to another in the water cycle, the path it can take is variable. Energy, in the form of heat, directly influences the rate of motion in water molecules. As molecules speed up with increased energy the state of the water molecules will change. Water molecules have three states: solid (ice), liquid (drinking water), and gas (water vapor). Often physical movement of water follows a change in the state of a water molecule. For example glaciers (solid) melt to pools (liquid) which flow to streams, where water may evaporate (gas) into the atmosphere. Regardless of the state of matter, water as a solid, liquid, or gas has mass and is subject to gravitational force. Gravity further influences the ability of water to travel over, under, and above the Earth s surface. This is the case with snow on mountains melting and descending through watersheds to the oceans of the world. Liquid is the most visible state of water. Water is seen flowing in streams and rivers, and tumbling in ocean waves. Water travels slowly 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 as water is constantly evaporating, changing from a liquid to a gas or a solid to gas. Water vapor travels through the atmosphere and surrounds us all the time. Where water vapor condenses, or cools, and returns to Earth depends upon loss of heat energy, gravity, and structure of Earth s surface. Water condensation can be seen as dew on plants or water droplets on the outside of a glass of cold water. In clouds, water molecules collect on tiny dust particles. Eventually, the water droplets become too heavy and gravity pulls the water molecules to Earth.

2 Lesson Plan 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 food during digestion. Water is excreted as a liquid or leaves as a gas, through perspiration or respiration. However, plants are the greatest movers of water. Roots absorb water and through transpiration water travels up through the xylem to the leaf surface. When water reaches the leaves, it is exposed to the air and sun s energy and is easily evaporated. All of these factors work together to move water around, through, and over Earth. Discuss & Investigate! 1. Tell students they are going to investigate the movement of water molecules through the water cycle as a water molecule. 2. Brainstorm with students all of the states water can take on during the water cycle. Water can be a gas, a liquid, and a solid. 3. List of the places that water travels and some of the things that impact how and where water travels. Water moves through the water cycle as vapor in clouds; through plants and animals as both vapor and a liquid; as liquid in rivers, lakes, ground water, oceans, and soil; and as a solid in glaciers and icebergs. 4. Discuss the conditions that cause the water to move. Explain that water movement depends on energy from the sun, electromagnetic energy and gravity. Sometimes water will not go anywhere. 5. Write these factors (clouds, plants, animals, rivers, lakes, ground water, oceans, soil, and glaciers) on large pieces of paper and put them in locations around the room or yard. Put a box of different colored beads at each station (e.g. green beads to represent plants or red to represent soil). 6. Have students take one piece of string and different color bead not found at the stations. Students should tie this bead to the end of their string to help keeping beads collected during the activity from dropping on the ground. 7. Tell students that as they become water molecules they will take a bead each time they go to a station to track where they have been. They will document their journey by the beads they collect and by writing a story as they move from station to station. Be sure students know they need to record the state (solid, liquid, or gas) of the water molecule as it travels to and from the various stations. 8. Assign an even number of students to each station, or have the students pick the station they want to start from. 9. As a group, have students list the different places in the water cycle a water molecule can travel from their station. After students have come up with lists, have each group share their work. 10. Once all groups have shared, pass out the nine dice to the appropriate station. Instruct students to each take a turn rolling the dice and then moving to that station. 11. After a student has rolled the dice, he/she should identify how (what state) the water

3 molecule will move to the next station either as a solid, liquid, or gas. a. Note: most of the movement will be done in the form of a liquid. 12. If a student rolls a Stay, he/she should pick another bead, go to the back of the line, and roll again. 13. When students arrive at the next station he/she should go to the back of the line, pick another colored bead and roll again. 14. Tell the students once they have collected 10 to 20 beads to have a seat in a designated area until all the students have at least 10 beads. Wrap up & Review! Have students write a short story (or complete their story) about where they have traveled as a water molecule, make sure they talk about how they didn t travel if they were stuck at a station for a long time. Teacher Tips Station Dice Labels Lesson Plan Soil Plant River Plant Water is absorbed by plant roots. River The soil is saturated and water runs off into a stream. Ground Water Water is pulled by gravity and filters into the soil. Stay Water remains on the surface e.g. in a puddle, adhering to particles in the soil. Stay Water is used by the plant and stays in the cells. Stay Water is used by the plant and stays in the cells. Lake Water flows into a lake. Ground Water Water is pulled by gravity and filters into the soil. Ocean Water travels to the ocean through a rivers watershed. Animal A thirsty animal takes a drink from the water. Stay Water remains in the river.

4 Clouds Lesson Plan Soil Water condenses and falls to the ground. Glacier Water condenses and falls as snow onto a glacier. Lake Water condenses and falls into a lake. Ocean Water condenses and falls into the ocean. Stay Water remains as a droplet clinging to a dust particle. Stay Water remains as a droplet clinging to a dust particle. Ocean Lake Ground Water Water is pulled by gravity and filters into the soil. Animal A thirsty animal takes a drink from the water. River Water flows into a river. Stay Water remains within the lake. Stay Water remains within the lake. Animal Soil Water is excreted through feces and urine. Soil Water is excreted through feces and urine. Clouds Water is respired or evaporated from the body. Clouds Water is respired or evaporated from the body. Clouds Water is respired or evaporated from the body. Stay Water is incorporated into the body and remains in cells. Ground Water River Water travels to a spring that flows into a river. Lake Water travels to a lake. Lake Water travels to a lake. Stay Water remains in the ground water. Stay Water remains in the ground water. Stay Water remains in the ground water. Glacier Ground Water Ice melts and water filters into the ground.

5 Lesson Plan Clouds Ice evaporates and water goes to the clouds (sublimation). River Ice melts and water flows into a river. Stay Ice stays frozen in the glacier. Stay Ice stays frozen in the glacier. Stay Ice stays frozen in the glacier.

6 Name: Write your story here about your journey as a rain drop: Date: Student Worksheet: Journey of a Rain Drop US Fish & Wildlife Service and