Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
UNIT: Water
LESSON # 4
TITLE: Water and Life
Summary: Children will answer the question, “Why
do living things need water?” It has two
active parts and a discussion. Children
will start with looking at how plants take
up water by doing the classical celery in
colored water activity. This will require
saving materials to view in the next
session. Next, children will do a simple
activity to get across the idea that many
chemical reactions (particularly
biochemistry) need water to happen.
NASA Source: Adapted from many non-NASA sources. A
good one for celery and food coloring is at
http://tinkerlab.com/celery-experiment/
For the biochemistry and water activity see
Science by Email at
<http://www.csiro.au/helix/sciencemail/a
ctivities/chillingrecipe.html>
Grade level: K-2
Time: Total time: 70 minutes
Snack & introduction: 15 minutes
Celery & food coloring: 10 minutes
Biochemistry & water: 20 minutes
Summary and cleanup: 25 minutes
1
Materials:
for celery and food coloring
activity
Item
Stalks of celery
with leaves
Clear tall
plastic cups
Blue food
coloring
Red food
coloring
Water
Quantity
per trio
2
2
5 drops
5 drops
2 cups
for biochemistry and water
activity
Item
Quantity
per trio
1
1 tbs.
Ziploc bag
Sodium
bicarbonate
(baking soda)
Citric acid *
1 tbs.
Tablespoon
1
Water
about 1 tbs.
*Read more: How to Buy Citric
Acid Powder | eHow.com Citric
acid is very safe. It is often used
in candy to make it sour.
Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
Children Children will learn that:
Learning  Most animals (including humans) and
plants need water.
Outcomes:
 Plants take up water through their
stalks.
 One reason living things need water is
to allow biochemical activity to take
place.
Children will engage in and thereby
strengthen a number of scientific
practices such as:
 Observe the effects of water on plants
and chemicals.
 Verbally communicate ideas about
water and living things.
Big Questions:
Lesson format:
National
Standards
Addressed:
Children will be able to (cultural goals):
 Relate overall science learning goals to
the context of their schools, families,
and community.
 Communicate ideas, collaborate with
other children, and learn in a
personally meaningful way.
 Why do you think we need water? In
what ways do animals (including
humans) use water in their bodies?
 Why do you think plants need water?
 In what ways do plants use water?
Hands-on activity and discussion.
This activity relates to the following
standards from the Next Generation
Science Standards:
K-LS1-1. Use observations to describe
patterns of what plants and animals
(including humans) need to survive.
2-LS2-1. Plan and conduct an
investigation to determine if plants
need sunlight and water to grow.
5-LS1-1. Support an argument that
plants get the materials they need for
growth chiefly from air and water.
2
Take-home KIT per child:
Each child will receive:
1 simple weather chart with the
following directions :
 Talk to your family members
about the weather. What do
we do to adjust to the weather
this time of year?
 Is the weather we experienced
this week normal for this time
of year? If it was different,
how was it different?
 What do you do when the
clouds give us rain or snow?
 What is your favorite kind of
weather? Why?
 Please remember to bring in a
show and tell object that
makes you think about water
or a drawing related to water
for next week.
Word Wall:
Include following words in
discussion (in both English and
Spanish), orally defined in
understandable terms, and
visibly displayed. If possible,
project a large image of the
words (and associated pictures)
on the wall of the teaching area
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Celery
Food coloring
Capillary
Baking soda
• Apio
• Colorantes
• Capilar
• Bicarbonate
de sodio
 Citric acid
• Ácido cítrico
 Chemistry
• química
 Biochemistry • Bioquímica
Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
DIRECTIONS:
Overview: This session involves four parts and one take-home activity:
1) Give children an opportunity to share show and tell object or drawing that makes
them think about water. Then start with a brief multimedia presentation and
introduce the topic of water and life.
2) Children then start the celery and food coloring activity.
3) Children do the water and biochemistry activity.
4) Facilitator talks with children about water and life.
5) Instruction for Take-home Kit/activity
Steps:
LESSON INTRODUCTION (10 minutes)

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Give children an opportunity to briefly share their show and tell object that makes
them think about water or their drawing related to water that was part of last
week’s take home.
At the beginning of the session (during snack, if provided), show a multimedia
presentation from Sesame Street to introduce today’s lesson.
http://www.youtube.com/watch?v=-vm-FcK4FbI

Tell the group that today’s lesson is about living things and water.

Relate today’s topic to the last lesson (clouds). They will switch gears to think about
water and life today. Remind the kids that by learning about water, they will gain a
better overall understanding of climate change, because air is one of the important
elements of our environment.

LESSON LEARNING TASKS (30 minutes)
Procedures
Celery and Food Coloring (10 minutes)
Start with a whole group demonstration. Tell the children that they will do an
experiment to see how water moves in plants. Ask for some of their ideas about how
they think water gets from the ground to the leaves. Tell them they can see how this
works with celery.
1. Fill the cup about three-quarters of the way to the top with water.
2. Add 5 drops of food coloring, red in one cup and blue in the other. Stir until
the color is evenly distributed throughout.
3. The facilitator will cut about 2.5 cm off the bottom of the stalk of celery with
the knife and the child will place the celery in the cup with the leaves sticking
up.
4. Check the stalk at the end of the session. Observe how the leaves are changing.
Let the stalk sit in the food coloring and place the cups where children can
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
view them. Ask the children to come back and observe a few days during the
week.
5. Discuss what happened at the beginning of next week’s session.
Biochemistry and Water (20 minutes)
This session will help children see that for something to happen when you mix
chemicals, sometimes you need water.
Tell the children:
1. In living plants and animals, things mix together and chemistry takes place to
do things like digest food, build the parts of the plants or animals and make
the energy things need to live. This experiment helps us see why water can
help with that process.
2. Pass out the materials to each group except for the water. Tell children that
they will be mixing baking soda, like is used in the kitchen (show a box if you
have one) with the stuff they add to sour candy that makes it sour. That stuff
is called citric acid [ácido cítrico.]
3. Have each group mix a tablespoon of citric acid powder and a tablespoon of
baking soda in the Ziploc bag and mix it together using their finger on the
outside of the bag to do the
mixing. (They should notice
that nothing much happens.)
4. Now have each group add
about a tablespoon of water.
(Children should notice that
bubbles are produced and
the bag fills with a gas. They
will also probably notice that
the bag gets cold.)
Ask the children what happened
when they mixed the dry
ingredients together? (Nothing.)
Then ask what happened when
they mixed the dry ingredients
with water? (Bubbles appeared,
the bag filled with a gas and the
bag got cold.)
[Children might wonder what
would happen if you mixed water
with just one of the powders. Have
materials on hand so that one
group can try the baking soda and
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
the other can try the citric acid powder. (They will see that nothing happens besides
the powders dissolving.)]
Tell the children that what they saw is chemistry—things mixing together to make
something new, like the bubbles.
In living things lots of chemistry happens that keeps us alive. It is called
biochemistry. Like in our experiment, that biochemistry needs water to help it
happen.
LESSON DISCUSSION AND SUMMARY (25 minutes)
Ask children why they think people and other animals need to drink water? What does the
water do in our bodies?
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Use this information as needed in the discussion
The human body is about 70% water. Every system in our body uses water.
Water makes all the body chemistry possible.
Water makes up almost 80% of our brain.
Water makes up 83% of our blood.
Water makes up nearly 90% of our lungs.
Water transports body wastes (think pee!).
Water lubricates body joints.
Water keeps body temperature stable (think sweat!).
Water aids in digestion (think spit!).
Human beings can live several weeks without food but only four to seven days
without water, depending on conditions.
We must drink six to eight glasses of water each day to replace the water we lose
from normal activity. Some water loss is visible through sweat and excretion.
Ask children where they get the water that their body uses. (Most will know that they drink
water.)
Ask them what else gives them water? Tell children that they also get water from drinking
milk, fruit juice, etc. They also get some water from the food they eat. Give an example of a
juicy piece of fruit.
Review word wall words while discussing observations children had about their activities.
Finish recording observations, collecting samples, and making drawings in journals. Make
sure to look at the celery one last time before leaving.
Clean up and put materials away.
TAKE HOME
Children will take home a simple weather chart and a sheet of paper with suggested
discussion questions to ask family and friends (in both English and Spanish). Introduce the
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
Take-home activity with a short discussion on “Where does the water in your home come
from, where does it go? From what do you get the water you need?”
Weather discussion. Give children a simple weather chart, including symbols for sunny,
partly sunny, cloudy, wind, rain, snow, and lightning. Include symbols for temperature
(hot, warm, cool, cold). On the weather chart, ask the children to record the weather for
that week with their families.
 Talk to your family members about the weather. What do we do to adjust to the
weather this time of year?
 Is the weather we experienced this week normal for this time of year? If it was
different, how was it different?
 What do you do when the clouds give us rain or snow?
 What is your favorite kind of weather? Why?
 Please remember to bring in a show and tell object that makes you think about
water or a drawing related to water for next week.
From this lesson, children should have learned:
 Most animals (including humans), and plants need water.
 Plants take up water through their stalks.
 One reason living things need water is to allow biochemical activity to take place.
ASSESSMENT:
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Ongoing, through the discussion and activities: monitor children’s usage and
understanding of words and ideas related to today’s lesson. Ask supporting questions
to encourage children to make connections. Clarify misconceptions.
Demonstrations of understanding: do any drawings, writing, theater, etc., display
sophisticated, accurate understanding of today’s lesson? Were children able to make
personal connections to the ideas? Were children able to make connections to prior
lessons?
Take-home work (assessed following week): did children follow through and discuss
the lesson with their families, bring a related show and tell object, and/or make a
drawing/other art project related to today’s lesson? Did discussion around these things
show continuing understanding of the ideas, including making connections to prior
lessons and to community?
Do children’s understandings, as displayed by their demonstrations of understanding,
questions, and discussion show connections between today’s topic, and the big picture
of the unit topic?
Photograph objects and save drawings brought in for sharing in individual child’s
portfolio. Do the artifacts in the portfolio demonstrate an increasing trajectory of
understanding about the elements of the Earth System over time? Do children show
understanding of climate change? Do children show personal connections, including
self, school, family, and community, to their understandings of climate change?
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
RELATED NASA ACTIVITIES AND RESOURCES:
Water: The Molecule of Life - An Interview with Philip Ball
http://www.nasa.gov/vision/universe/solarsystem/Water:_Molecule_of_Life_prt.htm
An interview with science writer about the importance of water in life.
NASA SCIENCE: Earth: Water Cycle
http://science.nasa.gov/earth-science/oceanography/ocean-earth-system/ocean-watercycle/
The water cycle is discussed with some focus on life, but an important reminder of the big
picture.
Earth Observatory: The Water Cycle
http://www.earthobservatory.nasa.gov/Features/Water/
Good information about the distribution of water on the planet.
BACKGROUND INFORMATION:
Without water the Earth would not have any plants or animals or humans. All life depends
on water. Next to the air we breathe, water is our most essential element of life.
Plants and animals, including humans use water in many ways. Note that the information on
how plants and animals use water is written at the adult level. You need to use your best
judgment when deciding how to talk about these things with children.
How do plants use water? They use water as follows (see
http://www.letusfindout.com/why-do-plants-need-water/):
1- Solvent:
Minerals in the soil can dissolve in water. When plants take up water, the minerals
dissolved in the water can also enter the plants body. In their regular solid state, these
necessary plant nutrients could not be taken into the plant.
2- Transport:
Water is used to transport the things in the plant from one part to the other where they are
needed. So it acts as a vehicle for the transportation. (See the celery and food coloring
activity.)
3- Photosynthesis:
Photosynthesis is a process in plants to make their food. Water is a necessary ingredient in
the formation of glucose via photosynthesis.
4- Evaporation:
Water is evaporated through the stomata present on the leaves in a process called
transpiration. It cools the plant in hot days, very much like we get cool by perspiration.
Evaporation is also necessary for plants to let the stomata remain open to take in carbon
dioxide.
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
5- Turgidity:
Water is necessary for the turgidity (like rigidity but more flexible). The pressure of water
in the cells of plants is important for the survival of plant or else it will wilt. It is also
required for the growth as it expands the plant cells.
In the celery and food coloring activity students see how water is transported in a plant. In
plants, water is absorbed from the soil into the roots of a plant. Water must move upward
to the top of the plant to reach the leaves where photosynthesis takes place. Water travels
through long, thin tubes running up from the roots through the stems and leaves called
xylem.
Water moves up the xylem through a process called capillary action. Capillary action allows
water to be pulled through the thin tubes because the molecules of the water are attracted
to the molecules that make up the tube. The water molecules at the top are pulled up the
tube and the water molecules below them are pulled along because of their attraction to
the water molecules above them.
Plants get rid of this extra water by transpiration. During transpiration, water evaporates
from holes in the surfaces of leaves into the air. As water evaporates from plant leaves, it
leaves spaces that attract the water molecules still in the plant. This helps pull water up
through the stems from the roots.
How do humans and other animals use water? They use water as follows (see
http://wiki.answers.com/Q/How_does_human_body_use_water):
1- As a medium of transport:
Water is used in the body to transport different molecules, cells and other materials. The
plasma which constitutes of nearly 55% of fluid part of blood contains 90% water. All this
water is used in transport of various materials like Blood Cells, Hormones, etc., throughout
the human body.
2- As a solvent:
Water is a universal solvent. It is used in the body to dissolve many things such as sodium
chloride and other salts. It can also dissolve urea and things like uric acid and is essential
for getting rid of these compounds.
3- As a metabolite:
Water in the body is also used as a metabolite and is used in many reactions. Also the
reactivity of many compounds increases when they are dissolved in water. This is
illustrated in our activity.
4- Mobility of Spermatozoa:
Spermatozoa can only move by their flagella in water. Therefore, water is necessary for
fertilization.
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
5- As a Coolant:
Water is also used as a coolant in the body, particularly in very hot conditions. When we
sweat the water from our skin evaporates and produces a cooling effect.
6- As a lubricant:
Water is used as a lubricant in the human body during digestion. The water in saliva
lubricates the food and makes it easier to pass to lower digestive tract. In addition to this
water around our different body parts such as eyeballs, muscles and joints allows a
friction-less movement.
Perhaps the most important aspect of water and life is that water is necessary for
biochemistry to take place. Biochemistry encompasses everything from photosynthesis to
formation of proteins and the production of useable energy from food. The biochemistry
and water activity illustrates that some chemistry cannot take place without the presence
of water.
The vast majority of the Earth's water resources are salt water, with only 2.5% being fresh
water. Approximately 70% of the fresh water available on the planet is frozen in the
icecaps of Antarctica and Greenland leaving the remaining 30% (equal to only 0.7% of total
water resources worldwide) available for consumption. From this remaining 0.7%, roughly
87% is allocated to agricultural purposes (IPCC 2007). This distribution and the necessity
of water for living things highlights how precious access to fresh water is.
CULTURAL BACKGROUND INFORMATION:
Water is one of the natural resources present in all aspects of human civilization.
Historically, the need and demand for water has been one of the driving forces for social
organization, economic prosperity, culture, development and health.
Then and now, the efficient use of this resource largely determines how one perceives,
assesses and manages it. Its effective use represents individual and collective well-being of
communities.
Historically, communities of the world honored and worshiped this important natural
resource. In its unique way, they created stories, gods, symbolisms and characters that
highlighted its importance:
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To most Native American tribes, water was used as a clan symbol. To the Hopi,
Navajo, and Pueblo tribes the water clan named is Piikyasngyam.
To Peruvians, the god of water was Naylamp. It was believed that Naylamp came
from the sea, and brought civilization to the lands of Lambayeque.
To Hindus, Ganga was the goddess of the Ganges river and is represented ridding a
sea monster.
In Norse mythology, Ægir is the king of the sea, and is a personificates of the power
of the ocean.
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
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To Greeks, Neptune governed all waters and seas.
To Mayas, Tlaloc (sometimes called Nuhualpilli) was the Nahuatl name of the God of
water and fertility in Teotihuacan and Nahuatl religions.
For the Egyptians, Sobek - was the water God. They believed that the Nile water
came from the sweat of Sobek and he was the god of all surface water.
To Japanese, Kappa is a mythological creature that lives in lakes, rivers and
wetlands.
The list goes on! Make sure to encourage your students to do a little research on a culture
of their choosing.
LESSON CONNECTIONS
This lesson is tied to ideas in other lessons:
In Lesson 1 (Evaporation), children are introduced some basic ideas about evaporation and
water vapor.
In Lesson 2 (Condensation and the Water Cycle), children learn some basic ideas about
condensation and how water vapor changes to liquid water. This is followed by using this
understanding of condensation and what children learned about evaporation in the last
session to introduce the water cycle.
In Lesson 3 (Clouds), children gain some basic ideas about what clouds are and how they
form, drawing from what they learned in the previous two lessons (on evaporation and
condensation). The lesson starts with everyone watching the first 2 minutes of a NASA
video on clouds. Then each group does an experiment, assisted by the facilitator, where
they make a cloud in a bottle.
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