EVAPORATION
STATION
You will need: "This is the Ocean" by Kersten Hamilton, several
wide mouth clear plastic jars or clear deli containers with lids, a
sunny window or a sun lamp, salt, soil from the playground or your
yard, local vegetation or lettuce leaves, a pitcher of ice water, and a
tall glass. Plan on leaving your experiments in the sun for several
hours. If you live in a very arid area, you may want to run a
humidifier in the class for an hour before you read the book.
Before you open the book, pour yourself a glass of ice water, and take
a drink. Set the glass somewhere close at hand and continue.
Read the book through once, focusing on the language as you show the
illustrations.
After reading the book, return to the illustration on pages 1 and 2
and ask, "Have you ever been to the ocean?" What did it smell like?
What did it sound like? (let the students imitate ocean sounds) Did
you swim in it? What did it taste like? (salty) Was it good to
drink? (No!) We can't drink salt water!
Turn to the illustrations on pages 3 and 4. What kind of
creatures do you see in this picture? (K-1 may just name
the creatures, 2-4 may want to classify) Can you find a reptile? (the
turtle) And look at this! (point at the octopus) Does
anyone know what kind of animal an octopus is? ItŐs a cephalopod! What
else do you see in this picture that is alive? (fish, plants,
coral) Do you know what a mammal is? (a warm blooded creature
that breaths air and has hair - just like us!) Are there any
mammals in this picture? (the dolphin)
Turn to pages 5 and 6. Whales are mammals, too. All of these
creatures fish, reptiles, cephalopods, mammals, even the plants and
coral they all need salty ocean water to live!
Turn to pages 7 and 8. Did you ever find anything mysterious on
the beach? Where did it come from? Why doesn't the water come up out of
the ocean, onto the land? (the land is higher)
Turn to pages 9 and 10. How does water get from the ocean to
the sky to become clouds? (The sun heats up the ocean. This causes
water vapor to rise into the sky.) That's called evaporation.
During evaporation, a liquid turns into a gas.
Hey! Look at my glass! (Point out the condensation on the
outside of your glass) Where did this water come from? (it came from
the air) Condensation is the opposite of evaporation. When
water heats up, a vapor rises from it. Tiny particles of water are in
the air all around us! When water vapor gets cooler like it did when it
touched my glass the water vapor condenses and comes out of the air.
That's just what happens when the water vapor rises up and gets
cooler. First it condenses into tiny particles. Millions and millions
of them together make a cloud. And then the particles join together to
make drops. Then we have rain! Rain is precipitation -water
falling from the clouds. Do you think rain is the only kind of
precipitation? (no) Can you name some other types of
precipitation? (snow, sleet, hail)
Turn to pages 11 and 12. How do the clouds move across they sky?
(the wind blows them) If we didn't have wind, the clouds would stay
over the ocean!
Turn to pages 13 and 14. Why do you think the rain is coming out
of the clouds? (the air rises and becomes cooler and drops
condense, just like they did on your glass)
Turn to pages 15 and 16. And the rain waters the trees and
plants...
Turn to pages 17 and 18. It fills brooks and pools. Look at
these thirsty mountain goats. I think they are glad that it rained.
Turn to pages 19 and 20. Are there any other creatures who need
the rain water? (fish, lady bugs, dragonflies.)
Turn to pages 21 and 22. This water looks like it is moving fast!
Why do you think it is splashing like that? (it is running down
hill)
Turn to pages 23 and 24. Wow! Even more creatures that need water!
Can you name them? (fish, beavers, birds.)
Turn to pages 25 and 26. Look at all these green fields! What kind
of plants do you think are growing here? (Corn, wheat, grasses,
etc.) All plants need water to grow. Have you eaten any plants
today?
Turn to pages 27 and 28. And then the water flows back into the
salty ocean again... Wait a minute!
Flip back to pages 17 and 18. These mountain goats can't drink salt
water(flip through the book, showing pictures as you go) these
birds can't drink salt water. Not even dragonflies can drink salt
water. Salt water would kill all of these plants. If this water came
from the ocean, what happened to the salt!! What do you think? (let
the class discuss)
This calls for some experiments!
Experiment 1: Why isn't rain salty?
Mix a teaspoon of salt into a quarter cup of water. Give each
student a swizzle stick and let them dip the tip into the water and
taste it. Record their observations. Pour the salt water into your
clear jar or plastic container. Cover and set in the sunlight or under
a sun lamp. When condensation has occurred, carefully remove the lid.
Allow students to taste the water from the lid using swizzle sticks.
Discuss your results: Do you remember what evaporation is?
(when a liquid turns into a gas). How do you think these drops of
water got from the bottom of our jar to the lid? (they turned into
a gas) Do you remember what condensation is? (it's the opposite
of evaporation-when a gas becomes a liquid) So... what do you think
happened to the salt? Why aren't these drops salty? (let
the students discuss) When the water turned into a gas, the salt
was left in the bottom of the jar because its evaporation temperature
is much higher than the water's.
Experiment 2: Is there water in dirt?
What about the water that sinks into the ground? Some of it flows
underground and eventually comes out into streams and rivers. Plants
absorb some through their roots. But what happens to the rest?
Is there water in dirt? How can we find out?
Take a soil sample from outside your classroom. Dig down several inches
for soil that rainwater could have seeped into. Put the soil into your
clear container and cover. Set the container in the sun or under a sun
lamp. Give the sun a couple of hours to work. Discuss the results: Was
there any water in the dirt? Results will vary, depending on your
soil. What happens to the rest of the water that sinks into the
ground? (let students discuss) Rain water soaks into the
ground, through the soil and deep underground to the rock layers, we
call it filtration. Some of this water will flow underground
until it comes back to the surface as springs.
As the water sinks through the soil and rocks, particles of
pollution and minerals that the water has picked up as it flowed over
the surface are filtered out. Filtration is an important step in
cleaning the earth's fresh water.
Experiment 3: What happens to water that is absorbed
by plants?
Plants soak up rain water through their roots. It travels up the
roots to the stem, and then to the leaves. What happens to the water
then? What happens if we forget to water our plants? (they wilt) Where
does the water they already soaked up go? (let the students
discuss)
Take leaves from plants around your classroom or from leafy produce
such as lettuce, place it a clear plastic container and seal it. Set it
in the sun or under a sun lamp. Give the sun a few hours to work, then
examine your experiment and discuss the results: Once the water
reaches the leaves, some of it evaporates. The evaporation of water
through plant leaves is called transpiration. In large forests
lots of water will transpire through leaves of the trees.
vocabulary words:
Evaporation: occurs when a liquid changes into a gas
Condensation: occurs when a gas changes into a liquid
Precipitation: water falling from clouds
Filtration: occurs when water sinks through rocks and sand
Transpiration: occurs when water evaporates from the leaves of
plants
BRAINSTORM A
RAINSTORM (Critical thinking skills)
This activity can be done together as a class exercise in critical
thinking, or as a small group project after completing Evaporation
Station. You will need a map of your area, including rivers, dams,
streams, forests, and mountains.
Lightning flashes! Thunder roars! The clouds open up and rain pours
down! Where did the water that is falling on you come from?
Where did the clouds form? Is it possible they formed over the
ocean? Why or why not?
Look at the map and describe where the water vapor that formed the
clouds may have come from. (Lakes, forests, rivers, damp soil from a
previous rain)
Do you think it is possible that you will end up drinking any of the
water that is falling from the sky? Why or why not? Where does the
water that falls on the playground go? How about the water that falls
on your town? Use the map to find any streams or rivers. Where do the
town's storm drains empty?
Where does your town get its drinking water? If we pour a glass of
water down the sink, where does the water go? Will somebody ever drink
it? Why or why not?
Suggested Books:
Literature Connection:
Storm Coming!: by Audrey B. Baird, Boyds Mills Press
Once Upon Ice: Jane Yolen, Boyds Mills Press
Snow, Snow, Winter Poems for Children: Jane Yolen, Boyds Mills
Press
Craft books:
Ocean Life: Thematic Arts and Crafts Activities for Young
Children: Louis Maes, MazeArt
Order from: Louis Maes
MazeArt
P.O. Box 11713
Albuquerque, NM
Nonfiction:
Air Is All Around You (Let's Read and Find Out Science Series):
Franklin Mansfield Branley, Holly Keller(Illustrator) Harper Trophy -
there is air in water too!
Exploring the Oceans : Science Activities for Kids: Anthony D.
Fredericks, Fulcrum Pub
Life in the Oceans: Lucy Baker, Scholastic Trade Paperback
WWW Sites:
Water: A Never-Ending Story Teachers' Resources:
http://www-k12.atmos.washington.edu/k12/pilot/water_cycle/teacherpage.html
Water Cycle Hands-on Activities:
http://www.teachtsp.com/classroom/scicourt/watercycle.html
USGS Water Science for Schools:
http://wwwga.usgs.gov/edu/earthwherewater.html
Theme Music:
Grand Canyon Suite: Ferde Grofe'
Appalachian Spring: Aaron Copeland
Under the Sea: Disney's Little Mermaid
Otopus' Garden: Raffi
Baby Beluga: Raffi
The Itsy Bitsy Spider
Down in the Meadow