Science
Grade 2
Unit 1
SOILS
(based on STC Kit)
INTRODUCTION
Soils can easily be described by their color, texture
and capacity to retain water.
Understanding soils helps us to also understand how the growth of
certain plants is supported or inhibited by where they grow and in what
substance. Soils support the
growth of many kinds of plants, including those in our food supply. Understanding the properties of soil
enables us to better understand the environment in which we live.
SCIENCE STANDARDS AND INDICATORS
Content Standard 2.3: Earth
materials have varied physical properties which make them useful in different
ways.
A21: Sort different soils by properties,
such as particle size, color and composition.
A22: Relate the properties of different
soils to their capacity to retain water and support the growth of certain
plants.
SCIENCE INQUIRY: Scientific inquiry is a thoughtful and coordinated
attempt to search out describe, explain and predict natural phenomena.
SCIENCE LITERACY: Science literacy includes speaking listening,
presenting, interpreting, reading and writing about science.
SCIENCE NUMERACY: Mathematics provides useful tool for the description,
analysis and presentation of scientific data and ideas.
EXPECTED PERFORMANCES
AINQ.2 Use senses and simple measuring tools to collect data
AINQ.4 Read, write and speak about observations of the
natural world.
AINQ.9 Count, order and sort objects by their
properties.
BIG IDEA
Soil is made of three
different things and supports plant life in different ways.
LINKS TO OTHER
STANDARDS
LANGUAGE ARTS
1.2.b. Interpret
information that is implied in a text
1.3.d. Develop
vocabulary through listening, speaking, reading and writing.
3.2.d. Research
information from multiple sources for a specific purpose.
Key Vocabulary: soil,
silt, clay, particles, properties, organic, textures, habitat, compost
ESSENTIAL KNOWLEDGE:
- Soil is a mixture of pieces of rock (particles)
living and once living things (humus), water, and air. The components of soil can be
separated using devices and settlement tests.
- There are different types of soil that vary from
place to place. Soil
properties can be observed and compared. Soils can be classified by properties such as color, particle
size, and amount of organic material. Digging a deep hole shows that soils are often found in
layers that have different colors and textures.
- The size of the particles in soil gives the soil
its texture. Soils can be
classified by how they feel; sandy soils feel gritty, silt feels powdery,
clay feels sticky and soils with small rocks feel rough and scratchy.
- The broken rocks that make up soils can be tiny
(silt and clay), medium (sand), or large (pebbles). Soils can be classified by the
size of their particles.
- A soil’s texture affects how it packs together;
soils that pack together tightly hold less air and water than soils that
stay loosely packed.
- There are different types of soil that vary from
place to place. Some soil
types are suited for supporting the weight of buildings and highways;
other types are suited for planting food crops or forest growth.
- Many plants need soil to grow because it holds
water and nutrients that are taken in by plant roots.
- Soil is a habitat for many living things. Some organisms live in the soil, while
others live on the soil.
Underground organisms adapt the soil to their needs.
- Plants that we eat grow in different soil
types. Plant height, root
length, number of leaves and flowers can all be affected by how much water
air and other organic materials the soil holds.
- To support the growth of different plants, people
can change the properties of soil by adding nutrients (fertilizing), water
(irrigating) or air (tilling).
CONCEPTS
- Soil contains particles of different sizes.
- Soil may contain animals, plants and their
remains.
- Over time, dead plants become part of soil.
- Composting, especially with worms, is an
effective way to recycle old plants and other discarded organic matter.
- Sand, clay and humus are three basic components of soil.
- Every soil component has unique properties that
can be identified using simple tests.
- Different soils absorb water at different rates.
- Many factors, including soil, effect plant and
root growth.
SKILLS:
·
Performing simple tests
to describe and identify soil components.
·
Observing, recording,
and organizing test results.
·
Interpreting test
results to draw conclusions about soil components.
·
Reflecting on test
results to predict how plants will grow in different so
·
Assembling laboratory
materials for soil experiments.
·
Communicating results
and ideas through writing, drawing and discussion.
·
Applying previously
learned concepts and skills to analyze unfamiliar soil samples.
ESSENTIAL QUESTIONS TO
GUIDE INSTRUCTION AND ASSESSMENT:
- What is soil?
- What is soil made of?
- What are the properties of different soils?
- Why do different plants grow differently in
different soils?
- How does soil hold water?
- How does soil support plant life?
- What factors regarding soil affects plant and
root growth?
MATERIALS AND SUPPLIES
OBJECTIVES AND GOALS
(as summarized from STC Kit, “Soils”)
LESSON ONE
What is in Soil?
- Students share what they show about soil and what
they want to find out.
- Students discuss the difference between a
prediction and an observation.
- Students predict what they will find in a sample
of garden soil.
- Students observe soil with a hand lens.
- Students compare and record observations of
garden soil.
LESSON TWO
Where do dead plants go?
- Students brainstorm where dead plants might go.
- Students set up a five-week composting project
using garden soil, worms and plant remains.
- The class sets up a compost bag without worms for
comparison (control).
- Students predict what will happen to the organic
matter in their compost bags.
- Students describe and record observations of
their organic matter.
LESSON THREE
Introducing Sand, Clay and
Humus
- Students discuss what they already know about
sand, clay and humus.
- Students examine sand, clay and humus with a hand
lens.
- Students touch, smell and listen to the three
samples.
- Students compare and discuss their observations.
- Students record their observations through
writing and drawing.
LESSON
FOUR
When Soils Get Wet
- Students describe the feel and appearance of
moistened sand, clay and humus.
- Students compare wet and dry samples, discussing
similarities and differences.
- Students discuss the results of rolling the moist
samples between their fingers.
- Students record their observations about moist
samples.
LESSON FIVE
More About Wet Soils
- Students conduct a smear test on sand, clay and
humus.
- Students record and discuss the results of the
smear test.
- Students observe and discuss changes in the clay
balls made in the last lesson.
- Students crush and moisten the dried clay balls
and discuss the changes.
- Students read about everyday uses for sand and
clay.
LESSON SIX
How Quickly Do Soils
Settle in Water?
- Students predict what will happen when they
separate soil and components by settling.
- Students observe and describe the results of the
settling test.
- Through drawing, students record their test
results.
- Students compare and discuss the results of
settling for the three samples.
LESSON SEVEN
More Settling a Few Days
Later
- Students observe further settling of sand, clay
and humus.
- Students discuss and record their observations of
settled materials.
- Students compare how the settled materials look
now with how they looked during the last lesson.
- Students observe the compost bags they set up in
Lesson 2.
LESSON EIGHT
What is Your Mystery
Mixture?
- Students conduct soil tests on an unfamiliar mixture.
- Students compare their test results with those
from their previous tests on sand, clay and humus.
- Students describe the properties of the new
mixture.
- Using their data, students infer which soil
components their mystery mixture contains.
- Students create a “mystery mixture” book with
their record sheets.
LESSON NINE
Growing Plants in
Different Soils
- Students discuss their ideas about plant growth
in different samples.
- Students plant seeds in sand, clay or humus and
their local soil.
- Students begin a logbook of their plants’
progress.
LESSON TEN
Why Do Plants Have Roots
in Soil?
- Students brainstorm what the roots of a plant do.
- Students plant seeds in clear tubes filled with
sand, clay and humus.
- Students monitor the growth of roots in each
tube, watering them regularly.
- Students observe and discuss changes in the
materials in their compost bags.
- Students read about earthworms and their
connection to plant roots and soil.
LESSON ELEVEN
Can Soil Hold Water?
- Students brainstorm a device to observe how water
moves through humus.
- Students compare the quantity of water added to
humus with the quantity that filters through.
- Students deduce where the missing water went.
- Students discuss how rain soaks into the ground.
- Students observe their planting cups and record
plant growth.
- Using a hand lens, students observe and compare
root growth in sand, clay, and humus.
LESSON TWELVE
How Water Moves through
Sand and Clay
- Students pour water simultaneously over samples
of sand and clay.
- Students observe, compare, and record how water
moves through the two samples.
- Students brainstorm how their experiment
resembles the effect of rain on soil.
- Students observe their planting cups and record
further plant growth.
- Using a hand lens, students observe and compare
root growth in sand, clay and humus.
LESSON THIRTEEN
Opening the Compost Bags
- Students observe, discuss, and record changes
that have occurred inside their compost bags.
- Students compare their predictions and findings
from earlier lessons to their observations today.
- Students compare the results of composting with
and without worms.
- Students read about making compost outdoors.
- Using a hand lens, students observe and discuss
root growth in sand, clay and humus, comparing results among the three
samples.
LESSON FOURTEEN
Exploring Your Local Soil
- Students review previous soil tests and their
results.
- Students examine the local soil and predict which
components it might contain.
- Students run tests on the local soil.
- Students discuss and record their findings.
- Students compare their test results today with
those from previous tests on sand, clay and humus.
- Students observe their planting cups and record
further plant growth.
LESSON FIFTEEN
More About Your Local Soil
- Students conduct additional tests on their local
soil.
- Students compare their current test results with
those from previous lessons.
- Students record their findings and share them
with the class.
LESSON SIXTEEN
What is Your Local Soil?
·
Students compare and
record plant growth in sand, clay humus and local soil.
·
Students complete their
plant logbooks.
·
Students make a class
chart to compare plant growth in the same kind of sample.
·
Students observe and
discuss differences in seedlings grown in the same kind of sample.
·
Students summarize their
investigation of local soil.
Students create a local soil
book with their record sheets.
RESOURCES
Web
Sites
·
http://soil.gsfc.nasa.gov/index.html
·
http://www.pedosphere.com/volume02/main.html
·
http://www.stormloader.com/geocoop/soils.htm
·
http://www.metla.fi/info/vlib/soils/old.htm
·
http://www.hintze-online.com/sos/soils-online.html
·
http://soil.gsfc.nasa.gov/env.htm
·
http://science.nasa.gov/headlines/y2006/28dec_truefake.htm
Literacy
Books
· Recycle: A Handbook for Kids by Gail Gibbons
· City Green by Dyanne DiSalvo-Ryan (Illustrator)
·
Cactus Hotel by Brenda Z. Guiberson
·
Growing
in the Garden: Outdoor Classrooms for Young Gardeners
·
Dirt
Made My Lunch by Banana Slug String Band
· Secrets of the Soil by Peter Tompkins, Christopher Bird
· Winter Wheat by Brenda Z. Guiberson, Megan Lloyd (Illustrator)
Extension Activities
·
Studying organisms that
you may find in soil, Appendix B
·
Sand Paintings, Appendix
C
Field
trips
·
Edgerton Park Greenhouse
·
Local Farm
·
Local restaurant that
uses a compost bin
Links
to United Streaming – www.unitedstreaming.com
Getting
to Know Soil (23:00)
Dr.
Dad's PH3: Episode Eleven: Soil and Agriculture (14:52)
Geologist's
Notebook: How to Make Mud Pie (11:00)
Worm
Farm (01:02)
Rocks:
The Solid Earth Materials #1 (20:00)