The Dirt On Soils
Teacher’s Guide
February 2011
Grades 5-8
5 Hours
Program Description & Standards:
Almost everything on earth can be called by another name – “temporarily not soil.” Explore the wonders of soil
while participating in an inquiry to uncover soil’s role as the foundation of all life. Unearth the secret soil
ingredients and recipe that interact to make our lunch.
Wisconsin Standards: Students show that earth materials have different physical and chemical properties,
including properties of soil found in Wisconsin. Students develop explanations for connections among living and
non-living things.
Focus Concept:
Soil is a group of interconnected components that supports all life, including us.
Essential Understandings, Processes and Skills:
Understandings:
1. Soils have many different ingredients (i.e. sand, silt, clay, organic matter, etc.).
2. Soils are formed by many different ongoing processes (i.e. decomposition, deposition, weathering, erosion,
glaciation and the activity of living things, etc.).
3. Soil structure results from the interaction of ingredients and processes.
4. Different soils are identified by chemical, physical and biological components.
5. Different soils support different types of communities.
6. Soil sustains life (plant growth, water purification, nutrient retention & cycling; and by providing habitat).
7. Living things, including humans, change the soil structure immediately and over time.
8. We are directly connected to soil through the air we breathe, the food we eat and the water we drink.
Processes and Skills:
1. Use scientific equipment such as soil probes, thermometers, pH kits and keys to explore soils in various
communities.
2. Learn how to identify organisms that live in soil.
3. Make observations and comparisons between soils in various communities.
Background:
Soil is a complex mixture of inorganic materials (pebbles, sand, silt and clay), decaying organic matter, water, air
and numerous living organisms. Soil forms when solid rock weathers and crumbles, life forms decay and
sediments are deposited by erosion. Bacteria, fungi, earthworms, ants, gophers and many other organisms live in
the soil and affect each part of it. These creatures add humus (a complex of minerals and organic matter) and help
speed up the weathering of rock particles. Soil is a result of mixing mineral (rock) and organic materials, for
example, by animals digging and storm-felled trees. It has biological, chemical and physical properties that are
always changing. Soil is the medium in which our food is grown and is the space where we build our towns and
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Copyright Riveredge Nature Center, 2004. This curriculum is for educational purposes only. Copy and/or distribution is not permitted.
cities. It provides habitat for living things, shelters plant roots and gives animals and some plants critical nutrients
for survival.
Vocabulary:
abiotic, acid, base (alkaline), biodiversity, biotic, community, compaction, consumer, decomposition, erosion,
humus, loam, organic matter, pH, parent material, percolation, producer, silt, soil, soil horizon, subsoil, topsoil
Preparation Activities at School:
Riveredge is a partner with you, the teacher, in creating a high-quality educational experience. We depend on you
to prepare your students for their hands-on activities at Riveredge. This preparation is essential to meet
curriculum goals. We are committed to excellence, so if you are unable to meet the minimum expectations in this
guide or have any questions, please contact a Riveredge educator at 262/675-6888 (local), or 262/375-2715
(metro).
Activities that should be done before the field trip:
1. Familiarize students with the enclosed vocabulary words and their definitions. For example, have students
create a mind map showing how the vocabulary words and concepts are connected.
2. What’s In Soil. This activity will help students become sharper observers and to begin to appreciate the life
soil harbors. Get a large bucket of soil from a garden, field or wooded area, or encourage students to bring in
samples from their own backyards. Cover the work areas with newspapers. Spread a handful of the soil on
the work areas and ask pairs of students to observe and describe the color, texture and odor while they
examine the components. Tell them to carefully separate the soil into two piles, using tweezers and
magnifying glasses. One pile should contain biotic matter such as plants and animals, either dead or alive,
and the second abiotic matter such as rocks, stones, clay, sand, etc. Allow the students to carefully add water
to their samples to discover how the properties of their soil change. Ask students to keep a list of the items
they find while dissecting the soil.
Fresh soil contains many different particles. These particles include tiny pieces of rocks, animals and humus.
All of these have broken down into very small pieces but may not be decomposed, so you can see what some
of the particles once were. The organic matter in soil provides plants with nutrients. Discuss what role each
of these components play. If possible, compare soil from a few different habitats such as a woodland, old
field, lawn and wetland.
3. Have your students draw a simple food chain, beginning with the plants and the successive animals that
depend on the plants for food. As it becomes clear how soil relates to humans, lead a short discussion on the
importance of soil for plants, animals and human survival. As they observed in the previous activity, soil
contains living and non-living things, water and nutrients necessary for life. Conclude by emphasizing how
soil is a group of interconnected components that supports all life, including us.
At Riveredge:
We will be outside most of the day, rain or shine! Older shoes and clothing are highly recommended. Boots can
be worn if rain is expected. Riveredge will supply rain ponchos if necessary. Sunglasses, cap with visor, sunblock,
and long pants and sleeves will prevent sunburn. It is the responsibility of the student to supply these things for
themselves. Please check the weather forecast and plan accordingly. Students should bring a bag lunch. A small
water bottle may be carried on the trail if desired.
Please meet the Riveredge Teacher Naturalists in the main parking lot in front of the Visitor Center. Classes will
be divided into smaller groups, each with their own Teacher Naturalist. This is best done upon arrival at
Riveredge when the number of students and Teacher Naturalists has been finalized. Please have your students
wear name tags. Riveredge will provide all necessary equipment. Each of the smaller groups will visit at least
two different communities. Our goal is to help the students understand that soil is a group of interconnected
components that supports all life, including us. The students will be involved in the following:
a. Sensory-awareness soil activities.
b. Investigations of soils and the factors that affect them. Students will formulate questions to investigate,
make observations and record their findings on a data sheet.
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Copyright Riveredge Nature Center, 2004. This curriculum is for educational purposes only. Copy and/or distribution is not permitted.
c. Interpretation of information. Students will analyze the information they collected and attempt to answer
their questions.
d. Presentations of their findings. Students will make decisions as to how to communicate their discoveries
to the larger group.
e. Identification of similarities and differences between the different soils and communities.
Follow-up Activities at School:
Choose one of the following activities to complete with your students.
1. Have students explore the relationship between plant growth and soil type by allowing them to mix their own
secret soil recipe, plant seeds and track their growth.
2. Set up a worm bin and begin vermicomposting (composting with worms) in the classroom.
Cooking With Soils: Experiment with Plant Nutrition.
Background:
This activity enables students to explore the relationships between plant growth and soil type by growing several
plants of the same species under identical conditions, but in different soil mixes. It will also help them uncover the
kind of information that helps farmers and gardeners grow the food we eat. They will gain experience setting up
an experiment, making and recording observations and measurements, and sharing their findings with classmates.
Students can record their secret soil recipe, observations, discoveries, results and questions they may have in a
journal.
Essential Understandings:
1. Soils have many different ingredients (i.e. sand, silt, clay, organic matter, etc.) and therefore have varying
amounts of nutrients, water-holding capacities, densities, etc.
2. Soil type can affect the rate of plant growth and general health of a plant.
Processes and Skills:
1. Students will learn how to set up an experiment, make and record observations, measure plant growth and
share their findings with others.
2. Students will gain experience keeping a journal.
To begin, each student should create their own soil recipe by measuring and mixing varying amounts of soil
such as sand, peat moss, garden soil, finished compost, clay or soil from the schoolyard, for example. After
mixing the components students should record the properties of their soil, including color, feel, water-holding
capacity, amount of organic matter and density. In order to test the recipe, plant several seeds of a fastgrowing plant (such as bean seeds or radishes) in each sample. For quicker germination, soak the seeds in
water overnight before planting. Be careful not to plant the seeds too deeply or the seedlings will take a long
time to emerge, or they may not sprout at all.
Sprout the seeds under exactly the same conditions of light, moisture, temperature, etc. Standardize the
amount of water the plants receive as well. Students should record when seeds sprouted, the rate of plant
growth and the general appearance of the plant, including height and the color, size and number of leaves.
Based on their observations and data, ask students to draw conclusions about their results. Be sure to include
time to allow them to discuss their findings with their classmates. The results will become more meaningful
after students have had an opportunity to compare their soil recipes and observations with each other. Use the
following questions to help guide the discussion: How do the plants respond to the different soils? How do
the height results compare with other indicators of plant health they observed? What did they find most
interesting or surprising? Do all plant species like the same recipes? How would they modify their recipe if
they could repeat the experiment?
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Copyright Riveredge Nature Center, 2004. This curriculum is for educational purposes only. Copy and/or distribution is not permitted.
Extensions:
A) Have the students make a graph of their results (plant height vs. time, for example).
B) Allow students to experiment with various types of nutrient additives such as a commercial fertilizer like
Miracle Grow, compost, worm castings etc. What affect did the various treatments have on plant growth?
C) Ask students to check the library or contact agricultural offices to find out the differences between farms
that use compost and manure as fertilizers, and those that use only chemical fertilizers. Ask students to
list the pros and cons of each approach (i.e. costs, environmental impact, quality and quantity of food
purchased). If possible, visit a local farm.
Adapted from Fast Plants/Bottle Biology.
After completing the experiments, send the class results to the Education Staff at Riveredge Nature Center.
Include a brief summary of the procedure they followed, their observations, the best soil recipes and other
interesting things they learned. If the students made graphs of their results, please send a copy of these as
well. Results will be posted on the Riveredge website.
Vermicomposting
Construct a worm bin for the classroom with your students and begin composting with worms. Vermicomposting
is a clean, simple process in which redworms and microorganisms transform food waste into a valuable fertilizer
for plants. The worms are kept in a covered bin with shredded paper or other biodegradable bedding and fed food
waste. They digest the food scraps and bedding then excrete nutrient-rich castings. Students will learn about the
decomposition process, worm anatomy and behavior, and much more. This interesting, year-round activity will
also help them to increase their environmental awareness. Many schools throughout the country have made worm
bins and their teachers report great success with the project. Please refer to the resource list at the end of this
guide for materials to help you get started. Contact a member of the Riveredge Education Staff if you have
further questions or would like information about how to obtain worms for your bin.
VOCABULARY:
abiotic A factor in an ecosystem that was never alive and which affects the organisms that live there. (i.e. water,
air, sunlight, soil, temperature, pH, etc.)
acid The name for a group of chemicals that taste sour, break up proteins, dissolve metals and conduct electricity.
Acids have a pH less than 7.
base (alkaline) A substance with a pH greater than 7 that often neutralizes acids.
biodiversity The sum total of all the living things in a particular area, all of their individual variations and all of
the interactions between them.
biotic The things in an ecosystem that are alive or were once alive.
community All of the plants and animals that live in a particular habitat and interact with each other.
compaction The size of the soil’s pores.
consumer An organism that cannot make its own food; it must find other living or non-living things to eat.
decomposition The process through which organic matter is broken down into simpler organic molecules by
decomposers who use the organic matter as food.
erosion The loosening and movement of rocks and soil by wind, moving water and ice.
humus A part of the soil containing highly decomposed plant and animal material.
loam A soil with a mixture of varying proportions of sand, clay and organic matter.
organic matter A mixture of plant and animal remains and the products of their decay.
parent material The mineral materials that break down to form soil.
percolation The downward movement of water through the soil.
pH The measuring unit to describe the acidity or alkalinity of a substance.
producer An organism that makes its food through the process of photosynthesis, usually a green plant.
silt Mineral particles in the soil, intermediate in size between clay and sand.
soil An always changing mixture of broken-down rocks, plant and animal material, air and water; the part of the
earth’s surface where plants grow.
soil horizon The layers in which soil naturally occurs, such as topsoil and subsoil.
subsoil The layer of soil beneath the topsoil.
topsoil The uppermost layer of soil that contains large amounts of organic matter.
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Copyright Riveredge Nature Center, 2004. This curriculum is for educational purposes only. Copy and/or distribution is not permitted.
Resources:
Bottle Biology Project. The Wisconsin Fast Plants Program, UW-Madison, Madison, WI. 1993.
Do We Treat Our Soil Like Dirt? National Geographic. September, 1984.
Earth Science For Every Kid. VanCleave, Janice. Wiley, New York City, NY. 1995.
Eco-Inquiry. Hogan, Kathleen. Institute of Ecosystem Studies, New York. 1994.
Ecology for Every Kid. VanCleave, Janice. Wiley, New York City, NY. 1996.
Everybody Needs a Rock. Baylor, Byrd. Scribners, New York. 1974.
Life In A Bucket of Soil. Silverstein, Alvin. Dover, New York. 2000.
Nature In A Nutshell For Kids. Potter, Jean. Wiley, New York City, NY. 1996.
Soil Science Simplified. Harpsted, M. I. and Hole, F. D. Iowa State University Press, Ames IA. 1988.
Soil -We Can’t Grow Without It -Educator’s Guide. National Wildlife Federation, Washington, D.C., March,
1985.
The Worm Book. Nancarrow, Loren and Hogan Taylor, Janet. Ten Speed Press, Berkeley, CA. 1998.
Worms Eat Our Garbage: Classroom Activities for a Better Environment. Appelhof, Mary, Mary Frances Fenton
and Barbara Loss Harris. Flower Press, Kalamazoo, MI. 1993.
WOW! The Wonders of Wetlands. Environmental Concerns, Inc. St. Michaels, MD. 21663. 1991.
WEB SITES
http://forces.si.edu/soils/03_00_00.html Smithsonian National Museum of Natural History, Explorers section provides
valuable background information on soil and introduces students to a wide range of scientists working in soil-related
fields through relevant case studies.
Rock Cycle:
http://www.cotf.edu/ete/modules/msese/earthsysflr/rock.html
A site covering the basics of the rock cycle.
Kids Gardening:
http://www.kidsgardening.com
This site provides hands-on activities to help further enhance student’s connection to soil.
Vermiculture/ Vermicomposting: using worms for composting
http://www.wormwoman.com
A site providing in-depth information on vermicomposting for the home or classroom.
http://www.wonderhowto.com/how-to-do-worm-wrangling-vermaculture-220372/ A how to video demonstrating
vermicomposting, from setting up the worm bins to the finished compost
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Copyright Riveredge Nature Center, 2004. This curriculum is for educational purposes only. Copy and/or distribution is not permitted.