Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
UNIT: Soil
LESSON # 1
TITLE: What Makes Up Soil
Summary: This lesson deals with the question, What Materials:
NASA Source:
Grade level:
Time:
Children
Learning
Outcomes:
is soil made of?” Children start by putting
soil in a clear bottle with water, shaking
the container and observing the soil
settling out into layers of sand, clay, silt
and organic material. Then, children put
together compost bins in which they can
observe decomposition of organic
materials over the course of the unit.
Adapted from NASA, Goddard Space Flight
Center’s “Soil Science Education” website
http://soil.gsfc.nasa.gov/index.php?sectio
n=7.
K-2
Total time: 70 minutes
Snack & introduction:
15 minutes
Shake bottle:
15 minutes
Compost bin:
25 minutes
Recheck shake bottle:
10 minutes
Journaling and cleanup:
5 minutes
Children will begin learning that:
 Soil contains sand, clay, silt, and organic
matter (humus).
 Humus is made via the decomposition
of organic material like plants.
Children will engage in and thereby
strengthen a number of scientific
practices such as:
 Raising questions about air and
observing the differences in the
components of soil in the shake bottle.
 Modeling formation of humus using
composting.
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
1
for shake bottle
Item
Quantity per
trio
1–2 oz clear
pill bottle
with
1
sealable cap
or similar
substitute
Loamy
enough to fill
topsoil*
bottle 2/3 full
Water
enough to fill
bottle
Liquid
about one drop
dishwasher
per bottle
detergent
Have one water pitcher for the
facilitator.
*Screened topsoil can be found
at landscaping or gardening
supply stores. (Loamy topsoil is
a good choice because it is not
dominated by one particle
size—sand, silt, or clay—and
should contain at least an
observable, small amount of
organic matter).
for 5-gallon compost bin
Item
Quantity per
group of 6–15
*5-gallon
bucket with
1
lid, black
Drip tray
1
3–4
Spacers to
Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
Big Questions:
Lesson format:
National
Standards
Addressed:
meaningful way.
 What is soil composed of?
 How is humus made (and what is it)?
Multimedia presentation, discussion and
hands-on activity.
This activity relates to the following
standards from the Next Generation
Science Standards:
5-LS2-1. Develop a model to describe the
movement of matter among plants,
animals, decomposers, and the
environment.
hold the
bucket
above the
drip tray
Vegetable
scraps/
coffee
2–3 gallons
grounds/
teabags/egg
shells
Newspaper
(to shred),
dry leafs,
2–3 gallons
twigs,
straws, etc.
Water in
1
spray bottle
* A drill with a ¼ inch bit is
necessary to prepare the bucket
If you cannot find a black bucket,
use black paint formulated to
stick to plastic to paint the
outside of the bucket.
Prepare the buckets before the
session. Drill ¼-inch holes about
2 inches apart in the side,
bottom and lid of the bucket.
Paint the exterior side and lid of
the bucket with black paint to
help your compost get warmed
by the sun.
Take-home KIT per child:
Children will take home a 1–2 oz
clear pill bottle with sealable cap
or similar substitute and a set of
instructions.
Word Wall:
Include following words in
discussion (in both English and
Spanish), orally defined in
understandable terms, and
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
visibly displayed. If possible,
project a large image of the
words (and associated pictures)
on the wall of the teaching area.
 Soil
 Sand
 Silt
 Clay
 Humus
(organic
material)
 Compost
• Suelo
• Arena
• Limo
• Arcilla
• Humus
(materia
orgánica)
• Abono
DIRECTIONS:
Overview: This session involves four parts and one take-home activity:
1)
2)
3)
4)
5)
Introduce the lesson with a multimedia presentation.
First, the children will separate the soil parts with a shake bottle.
Children will prepare a compost bin.
Children will reexamine their shake bottle and draw what they see.
Instruction for Take-home Kit/activity.
Steps:
LESSON INTRODUCTION (10 minutes)


Tell children that today, we will be starting to learn about soil (another name for
dirt). Tell the children that by learning about soil they will gain a better overall
understanding of climate change, because soil is one of the important elements of
our environment.
Then, (during snack, if provided), show a multimedia presentation to introduce
today’s lesson using the video at:
http://forces.si.edu/soils/video/secret_ingredient.html
LESSON LEARNING TASKS (60 minutes)
Shake Bottle (15 minutes)
Start by asking the group, “What is soil?” Take a few answers. If necessary, tell the
children that soil is another name for the dirt that they walk on, that things grow in and
that is under the grass. Show them a sample of the soil that will be used in the activity.
Ask for some of their ideas about what they think the soil is made up of. Tell them that
they will separate the parts that make up the soil in the first activity today.
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
1. Give each group of 3 children a bottle and cap. Have them label it with a symbol
that represents their group.
2. Show them how to fill the bottle 2/3 full of soil. Then have them do so with their
bottle.
3. Fill each bottle almost to the top with water and put the cap on tightly.
4. Have each child in the group of 3 shake their bottle for about 20 seconds.
5. Have each group put their bottle on the table and observe what is happening for
3 minutes. Walk around to the groups and ask them what they are noticing.
6. Have the children carefully (without shaking the bottles) set the bottles aside to
view later in the session. Tell them that it will take some time to let everything in
the bottle settle.
Composting (25 minutes)
Tell children that the material that they saw starting to float on the top of the shake
bottle is called “humus” and comes from decomposed or broken down plants. In today’s
activity, they will build a small compost pile. Over the next month or so, they will see
how dead plants (and things made from plants like newspaper) can break down and
decompose.
1. Have the children shred strips of newspaper and tear or cut the organic material
into small (1/2 inch) pieces. The small pieces will speed the composting process.
2. Layer organic material in the bucket—starting with shredded newspaper to
absorb moisture and create space for airflow. (Layers should be 2–4 inches
thick.) Add almost anything except animal products, but it is best to alternate
fresh vegetable scraps and other “green” stuff with dry leaves, shredded
newspaper or other "brown" stuff, to keep moisture levels ideal. Make sure that
there is enough “brown” material so the compost gets the air it needs and that
anaerobic (without oxygen) conditions do not develop. Insufficient air creates a
really smelly (ammonia-like) “goo pile”.
3. Sprinkle a handful of ordinary dirt (which contains the microorganisms needed
to get it your compost to start breaking down all the organic matter in there) on
each layer as you put it in. About halfway through, and again at the top, add a few
sprays of water. You do not want much water—better too dry than too wet.
4. Close the lid and place the 5-gallon compost bucket on a drip tray. Use spacers,
such as scrap wood, to lift the bottom of the bucket off the tray.
5. Place the composter in a warm place, preferably, in the sunlight.
6. Several times per week, shake or roll the bucket around to mix and aerate the
contents. If the bucket starts to smell or there is liquid draining from the bottom,
the mixture is too wet. Mix in dry soil or shredded newspaper. Also, remove the
lid and make sure the mixture has not totally dried out. If it is dry, give it a few
sprays of water.
7. Check the contents with the children weekly. They should see significant
decomposition and some completed compost after a month.
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
Reexamine Shake Bottles (10 minutes)
1. Have the children reexamine their shake bottles and discuss what they see. Have
them draw pictures in their journals.
2. They should expect to see layers of different components of the soil. Explain to them
what each layer is as follows.
Humus floating on
water
Clay
Silt
Sand
3.
4.
5.
6.
The layer on the bottom is sand. This has the largest mineral particles.
The next layer up is silt. This has particles smaller than sand.
The next layer is clay. This contains the smallest mineral particles in the soil.
There is some relatively clear water on top. Floating on the top of the water is some
organic material that comes from the humus in the soil.
LESSON SUMMARY (5 minutes)
Review word wall words while discussing observations children had about their activities.
Finish recording observations, collecting samples, and making drawings in journals. Clean
up and put materials away.
From this lesson, children should have learned:
 Soil is made up of sand, silt, clay and humus.
 Organic material can be broken down in the soil.
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
TAKE HOME
Each child will receive a 1–2 oz clear pill bottle with sealable cap or similar substitute and a
paper with instructions on how to do a shake bottle with soil near their home. The
direction sheet will say:
 Fill the bottle 2/3 full of soil from your yard.
 Fill each bottle almost to the top with water and put the cap on tightly.
 Shake the bottle for about 1 minute.
 Put the bottle on a table or counter top and observe what is happening for 3
minutes.
 Carefully (without shaking the bottle) set the bottle aside to view about 1 hour later
or more. It will take some time to let everything in the bottle settle.
 Observe the bottle and draw a picture of what you see paying particular attention to
the different layers within the bottle. The lowest layer is probably sand; next higher,
silt; then clay; and above the clearer water, there may be some organic material
floating.
ASSESSMENT:
 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?
RELATED NASA ACTIVITIES AND RESOURCES:
Soil Science Education
http://soils.gsfc.nasa.gov/
The portal to a large array of NASA education resources on soil.
Soil Science Education: Introduction to Soil Forming Factors
http://soils.gsfc.nasa.gov/index.php?section=78#earthdeposits
An introduction to learning about how the Earth deposits, minerals, parent material and
weathering work together to form and develop soil.
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
Soil Science Education: Soil Sizes – Some Surprises
http://soils.gsfc.nasa.gov/Sizes/
An activity related to the shake bottle activity.
Soil Science Education: Soil Microbes
http://soils.gsfc.nasa.gov/Microbes/
Discusses some of the microbes at work in compost pile.
BACKGROUND INFORMATION:
This chart is from http://soil.gsfc.nasa.gov/index.php?section=73 , part of NASA’s GLOBE Soil
Science Education program
The top layer of the solid surface of the Earth is called the pedosphere. This layer is
primarily made up of soil but also contains air, water and living things. The pedosphere is
critical to the Earth system as it is the prime interface between all parts of the system. It
interacts with air, water and important parts of the biosphere (living things) and is the
place where incoming sunlight is absorbed and transformed to heat energy.
The pedosphere serves a number of functions. It is home to plants and animals. It is a
medium for plant growth and critical for crop production. It adds particular gases to and
takes particular gases from the atmosphere including carbon dioxide and nitrogen. It
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
contains waste decomposing organisms. It filters water and removes waste. It provides
materials for building, pottery (e.g. clay), art (e.g. pigments), make-up and medicine.
The pedosphere is made of a combination of organic matter, minerals, water and air. There
are many living things in the soil from microbes, to plants and burrowing animals. The
minerals in the soil are produced from the breakdown of larger rocks. Clay, in addition to
being broken down rock, undergoes a reassembling into new structures. The mineral parts
of the soil are defined by particle size. According to the USDA, the soil parts are defined as:



Sand 2.00mm–0.05mm
Silt
0.05mm–0.002mm
Clay less than 0.002mm
The very fine organic material in the soil is called humus. Humus is plant and animal matter
in the soil that is broken down and reassembled into large stable molecules. Humus is
critical to the fertility of the soil.
The mineral part of the soil comes from breaking down “parent” material into very fine
particles. The parent material for soil in a particular place may come from rock, broken
down in place or deposits carried to that place by water, wind, glaciers, volcanoes or
rockslides.
The breakdown of parent material is done by weathering. Wind, rain, snow, heat, living
organisms (including bacteria, plants and people) can all break down rocks. Topography
plays a big role in this process. For instance, water running down steep mountainsides can
lead to rapid erosion and deposition. Weathering can also take place by chemical means.
For instance, natural processes can produce acidic rain. The acidic water then breaks down
rocks like limestone. Most of these processes are slow. The average time that it takes to
build up one inch of soil is 50 to 100 years.
Clay undergoes additional processes in its formation. Through physical and chemical
weathering nature can produce a microscopic mixture of flat, plate-like particles. These
form the basis of clay. They have a very large surface area that can serve to bind nutrients
and hold water in the soil. Clay is therefore, a very important ingredient for fertile soil.
The fine organic part of the soil, humus, is formed by breaking down of dead plants and
animals into simple organic components that reassemble into larger, more stable
molecules. The bulk of the final breakdown and reassembly is done by bacteria, fungi and
protists. These microorganisms use dead plants and animals for food that gives them
energy and building parts for their bodies. When the microbes die or are eaten by other soil
organisms, the nutrients in their bodies can be used by growing plants. Humus is made by
these organisms in a different process. In this process, soil organic matter is transformed
via extracellular “digestion” into more complex, stable humus particles.
Earthworms are very helpful in this process. Initially, most organic waste is composed of
pieces that are too large for microbes to effectively break down. Worms “chew” fresh
organic waste into small particles that are more easily broken down by microbes.
The decomposition of dead plants and animals is a natural process that is all around us.
Composing mimics this process. We gather dead plant material. We add microbes (from the
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Developed by CLACE- PI Marina La Grave, Dr. Barry Kluger-Bell and Kristine Johnson
soil) that do all the real work of breaking down everything into stable organic materials
and nutrients that plants can use. When these materials are completely broken down and
reformed, we have humus.
CULTURAL BACKGROUND INFORMATION:
Communities around the world have adapted their agricultural needs to its soils and
geography.
During pre-Hispanic times one of the methods of agriculture of ancient peoples of
Mesoamerica was by the system of "chinampas.” The Toltecs developed this system. A
“chinampa” is something like a floating garden that was planted on the banks of lakes. The
soil of a chinampa was obtained from the bottom of the lake, and thanks to its nourishing
properties, crops prospered and were able to produce up to 6 harvests per year. An
important fact of this practice is that a sustainable chinampas did not need watering, as
plants simply absorbed the water off the lake or from rain. “Ahuejotes”, (willow tress) were
planted on the banks of the chinampas in order to provide greater stability.
Many countries continue to use this sustainable ancient practice!
LESSON CONNECTIONS
The soil unit has two strands. The soil strand deals with what makes up soil and what soil
contributes to life. The transformation strand deals with change over time including how
soil is made and things growing in soil.
This lesson is tied to ideas in other lessons:
In Lesson 2 (What makes up soil), children learn some basic soil profiles and how rocks and
minerals are broken down into soil by weathering and other processes.
In Lesson 3 (What makes soil good for growing), children explore what makes soil that is
good to grow things in and how plant roots interact with the soil.
In Lesson 4 (What lives in the soil), children learn about things that live in the soil from
microscopic bacteria to worms and bugs to burrowing mammals like rabbits.
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