Third Grade - Science - Lesson 7 - Ecology

Objectives
Describe how energy moves through a food chain.
Create models of food chains in a pond ecosystem.
Describe how environmental changes might affect a pond ecosystem.

Materials
Pictures of pond plants and animals from Suggested Books
Sentence-strip tags with yarn loops to wear around the neck, marked producer, consumer 1, consumer 2, consumer 3, consumer 4, decomposer
A sentence strip crown with the word energy printed on it
Pond Food Web sheet for each student (see attached)

Suggested Books
Dewey, Jennifer. At the Edge of the Pond. Boston: Little Brown, 1987. Documents pond habitats from the muddy edges to the detritus at the bottom.
Downer, Ann. Spring Pool. New York: Franklin Watts, 1992. A look at the life in temporary vernal pools created by spring rains.
Emory, Jerry. Dirty, Rotten, Dead? New York: Harcourt, 1996. In addition to an excellent text explaining the role of decay in a regenerating cycle, Emory includes activites to demonstrate how decomposers work.
Fleming, Denise. In the Small, Small Pond. New York: Holt, 1993. Follows what goes on at a pond from spring to fall in a lilting text with simple illustrations.
Fowler, Allan. Life in a Pond. Chicago: Childrens Press, 1996.
Hester, Nigel. The Living Pond. New York: Franklin Watts, 1990. Sections on plants and insects have good color photos.
Hughey, Pat. Scavengers and Decomposers: Nature's Clean Up Crew. New York: Atheneum, 1984.
Humphrey, Paul. Below the Green Pond. Austin, TX: Raintree/Steck-Vaughn, 1996.
Lavies, Bianca. Lily Pad Pond. New York: Dutton, 1989. Excellent close-up photographs and short text describe the inhabitants of a pond.
Milkins, Colin S. Discovering Pond Life. New York: Bookwright, 1990. Organizes a pond community into plants, herbivores and carnivores. Includes a section on studying pond life.
Parker, Steve. Pond and River. New York: Knopf, 1988. As in all Eyewitness books, this one includes clear, stunning photos of plants and animals on white backgrounds.
Penny, Malcolm. The Food Chain. New York: Bookwright, 1988.
Rosen, Michael. All Eyes on the Pond. New York: Hyperion, 1994. Gets close-up and personal with a variety of pond creatures.
Schwartz, David. The Hidden Life of the Pond. New York: Crown, 1988. Highly recommended for its read-aloud text.
Silver, Donald. Pond. New York: McGraw-Hill, 1997. The newest addition to the acclaimed One Small Square series. Silver's text is always fascinating as well as informative. Illustrations are exceptional.
Stidworthy, John. Ponds and Streams. Mahwah, NJ: Troll Associates, 1990. Groups animals living in pond according to habitat. The section called "At the Surface" has especially good illustrations of water striders (also called pond skaters) and whirligig beetles. Many of the birds and mammals in this book are native to Europe.
Williams, Terry Tempest. Between Cattails. New York: Scribners, 1985. Although this beautifully written book explores a marsh and not a pond ecosystem, many of the inhabitants are the same. Certainly the concept of interconnectedness of a community is made abundantly clear.

Background Information
Ecology is the study of the interconnectedness of living things. It comes from the Greek word, oikos which means household. Ecologists study natural households or communities to find out how plants and animals relate to each other and their surroundings. They study how inhabitants of a community provide food, shelter and other things for one another.
An ecosystem is a natural community and its surroundings. A pond is an example of an ecosystem in which the web of life can be studied. Within the pond ecosystem, there are several habitats where plants and animals live: the pond edge, the bottom of the pond, open water and the surface of the pond. Mammals, fish, reptiles, amphibians, insects, birds and plants live in these habitats and play roles in the equilibrium of the pond ecosystem.
Plants and animals in any ecosystem can be divided into three groups according to their roles. Green plants are producers. Through photosynthesis, they capture energy from the sun and change it into food. Animals are consumers. They eat plants (herbivores) or eat other animals (carnivores) and energy is transferred from the producers to the consumers. Decomposers (scavengers, bacteria and fungi) break down dead plants and animals and recycle nutrients that plants can use to grow and produce more food. This transfer and recycling of the sun's energy fuels the natural world.
The natural world is dynamic, always changing. Due to changes in environmental conditions, both subtle and catastrophic, animal and plant populations grow and dwindle. Variations in supplies of food and cover, weather and climate, disease, enemies and natural disasters all can cause changes to an environment. Interdependence, adaptability, competition and grabbed opportunities determine what individuals and what species survive. Nature's equilibrium, or balance, is maintained by limiting factors. For example, when wolves were exterminated in Arizona, deer populations increased dramatically. With wolves eliminated as predators, more deer survived. The food resources for deer, however, did not increase. The larger population of deer browsed not only on mature trees, but also on very young trees that could not survive their browsing. Before long, the forest had thinned and there was not enough food to support the deer population. Many deer starved to death. The limiting factor of food supply kept the deer population in check.

Procedure
Remind the students that they learned about the five classes of vertebrates: fish, reptiles, amphibians, birds and mammals. Tell the students that there is something that all animals, both vertebrates and invertebrates do. They all eat. Ask: What do animals eat? (plants, other animals) Tell the students that animals eat, so they are consumers. Write consumer on the board. Remind the children that green plants make food. They capture energy from the sun and change it into food. Plants are called producers because they produce food. Write producer on the board. To get a plant's food energy, an animal eats it. Then energy moves from the plant to the animal.
Draw an arrow from producer to consumer on the board. Tell the children that when the plant eater is eaten by another animal, the energy moves from that consumer to another consumer. Write consumer 2 on the board and draw an arrow from consumer to consumer 2. Ask: What do you think happens to the energy when consumer 2 dies? (Accept all answers.) Tell the students that plants and animals called decomposers break down the dead body and recycle its nutrients into the soil or water so plants can use it to grow and make more food. Write decomposer on the board. Draw an arrow from consumer 2 to decomposer and an arrow from decomposer back to producer, forming a cycle. Tell the students that this cycle is how energy moves through a food chain. Ask: What is a food chain? (plants and animals linked together because each one is food for the next)
Tell the class that today they are going to create models of some food chains. Write producer, consumer 1(plant eater), consumer 2 (animal eater) and decomposer as headings on the board. Ask the students if they have ever visited a pond. Tell them a pond is not like a river or stream where the water is always moving. A pond is still and shallow and much smaller than a lake. Show the students pictures from Suggested Books of ponds and the plants and animals that live in or around a pond, for example, frog, tadpole, water strider, fish, dragonfly, turtle, duck, reeds and cattails, duckweed, snail, water boatman, water lilies, etc. If available, read aloud Lily Pad Pond by Bianca Lavies or The Hidden Life of the Pond by David Schwartz. Ask: What animals might visit a pond to hunt for prey? (snakes, herons, kingfishers, raccoons, maybe people with fishing rods) Brainstorm with the students and list on the board plants and animals that inhabit or visit a pond. Put them under the appropriate headings. Remind the students that there are several habitats or neighborhoods in a pond community. Some animals and plants live at the edges of a pond or visit it, some live on the muddy bottom, some in open water in the middle of a pond and others live on the surface of the pond (water strider and water spider).
Suggest making a food chain from the list. For example, the food chain might begin with some floating green plants in a pond. Ask a student to come up and be a floating green plant in a pond. Have him or her wear the producer tag. Tell the students that this green plant has been floating in the sunshine, gathering the sun's energy (place the energy crown on the student's head) and changing it into food. Up swims a tadpole to nibble on the green plant. Have a student come up to be a tadpole and wear the consumer 1 tag. Tell the students that the tadpole nibbled on the green floating plant and food energy moved from the plant to the tadpole. Place the energy crown on "tadpole's" head. Tell the students that along came a big fish and swallowed the tadpole in one gulp. Have a student come up, be a big fish and wear the consumer 2 tag. Place the energy crown on his or her head. Tell the students that the fish was a very old fish. Soon it died and its body fell to the bottom of the pond. There water beetles, worms and bacteria used the fish's body for food and broke it down into nutrients that floated in the water. Ask a student to come up, be a water beetle and wear the decomposer tag. Place the energy crown on the student's head. Tell the students that once the fish's body was decomposed, the nutrients in the water were used by floating plants to grow and make more food. Move the energy crown to floating plant-producer's head. Point out that energy has passed from floating plant to tadpole to fish to water beetle to floating plant.
Have the students devise other pond scenarios using different plants and animals listed on the board and perhaps creating longer food chains that use tags for consumers 3 and 4. For instance, suggest that if tadpole were eaten by a snake, a different food chain would be formed
(perhaps tadpole-snake-heron). Suggest that if tadpole grows up and becomes a frog, it might eat a dragonfly and then become food for a raccoon, making a different food chain.
Distribute the pond food web sheet (see attached). Point out how food chains connect in a pattern called a food web. All the animals and plants that live in a pond community are connected to each other through a food web. The food web is sometimes called the web of life. Ask: Looking at the pond food web, what do you think would happen if a pet store owner came to the pond and caught all the frogs, then took them back to his store to sell? (There would be no frogs in the pond.) Ask the students to put an X over the frog on the food web sheet. Have the students count how many kinds of animals that eat frogs would be hungry. (4) Suppose the frog eaters became so hungry that they died. Tell the students to draw X's over the frog eaters. Ask: If the frog eaters are gone, what happens to animals that eat the frog eaters? (They leave or starve.) Tell the students to draw an X over the animal that eats frog eaters (hawk). Remind the students that with no frogs to lay eggs, there won't be any tadpoles. Have the students draw X's over the frog eggs, tadpole, any frog egg eaters, tadpole eaters, and animals that eat tadpole eaters or frog egg eaters. Ask: Looking at the pond food web, what has happened to the pond community? (Many of the animals that live in the pond community have starved or left the pond.) Remind the students that plants and animals in a community are connected to each other. When something happens to one kind of animal, it can affect all the animals in that community and its web of life.

Possible Field Trip
Visit a pond at a park, nature center or the Baltimore Zoo. If possible, contact park staff or a naturalist to help the students safely explore the pond. Nature centers often provide materials to prepare the class for a visit and may help with dip nets and containers for examining pond inhabitants.
Ecologists who study ponds are called limnologists. Contact a limnologist at a local university. He or she might be able to speak to the class or steer you to a good pond to visit in your area.

Long Term Project
Introduce the idea of a long term project to the class. Explain that each student will be working throughout the month, putting together a project on an endangered animal. Each student will read books and collect information about the animal, about its habitat, what it looks like, what it eats and why it is endangered. At the end of the month each student will write a letter to his or her Representative in Congress or U.S. Senator. In their letters, the students will tell their representatives in Washington why they care about endangered animals and why it is important to protect them. Distribute the Long Term Project info sheet/checklist (see attached). The students' first assignment is to find out the name of their representative in Congress or their U.S. Senator and address an envelope to that person. You might want to review how to write an address and show an example of a correctly addressed envelope. To find the names of representatives and senators, call the Federal Information Center at 800-688-9889, The League of Women Voters of Baltimore City at 410-825-5353, or Enoch Pratt Information Services at 410-396-5430. Students can find out their Congressional Districts by looking at their parents' voters.

Third Grade - Science - Lesson 8 - Ecology

Objectives
Describe how changes in an environment can affect animal and plant populations.
Recognize the primary concerns of an ecologist.
Identify a variety of ecosystems.

Materials
Pictures of wolves from Suggested Books
Map of U.S.
Laminated cut-outs of trees (six), deer (seven), a wolf (see attached) and masking tape
Ecologists Notebook worksheet, one for each student (see attached)

Suggested Books
George, Jean Craighead. The Moon of the Gray Wolves. New York: Harpercrest, 1991. Follows a wolf pack in Alaska.
Godkin, Celia. Wolf Island. New York: W.H. Freeman, 1993. Tells the story of some island creatures who are affected by the disappearance of wolves on their island.
Hansen, Rosanna. Wolves and Coyotes. New York: Grosset, 1981. Good color illustrations and sections on wolf behavior and family life.
Hirschi, Ron. When the Wolves Return. New York: Cobblehill, 1995. Describes the efforts to restore wolves to their former territories.
Ling, Mary. Amazing Wolves, Dogs and Foxes (Eyewitness Junior series). New York: Knopf, 1991.
Patent, Dorothy Hinshaw. Gray Wolf, Red Wolf. New York: Clarion, 1990. Examines the life cycle and behavior of two types of wolves. Includes good color photos.
Patent, Dorothy Hinshaw. Return of the Wolf. New York: Clarion, 1997. This story is told through the eyes of a female wolf as she takes over a territory and establishes a new wolf pack.

Teacher Notes
Cut-outs can be laminated so they can be used from year to year. To save time during the lesson, write this list on a corner of the board: pond, forest, desert, stream, tropical rainforest, ocean, cave, mountaintop, underground, city.

Procedure
Remind the students that last time they learned that plants and animals in a community are connected to each other. What happens to one kind of animal in a community can affect the others in its food web. Ask: What happened to the pond community when all the frogs were taken away? (Other animals that ate frogs and tadpoles had no food and left the pond or starved. This meant animals that ate frog eaters or tadpole eaters had no food and left the pond or starved also.)
Tell the students that you are going to describe another example of what happens when a food web gets out of balance. This example starts with wolves. Ask: Are wolves carnivores or herbivores? (Wolves are carnivores. They hunt and eat meat.) Tell the students that wolves cooperate and hunt together in packs. Their packs are like families. When they work together, wolves can hunt and kill animals bigger than they are and get meat to feed the pack. Show the students pictures of wolves from Suggested Books. Tell the students that wolves are about the size of a German Shepherd dog.
Tell the students that in the last century, there were wolf packs in northern Arizona. Have a student come up to the U.S. map and locate Arizona. Tell the students that in the forests and meadows of northern Arizona wolves once hunted deer. Put a wolf cut-out on the board. Below it put three deer cut-outs. Tell them that the deer found food in the forest, nibbling moss, leaves and twigs. Put six tree cut-outs below the deer cut-outs. Try to arrange the cut-outs to form a pyramid shape. Point out that producers (the trees) fed the consumers (the deer) which fed other consumers (the wolves) making a food chain. Tell the students that people who lived in northern Arizona decided that wolves were a nuisance. They didn't like predators killing the deer they wanted to shoot as game. They thought the wolves threatened their cows and sheep. So they began hunting and shooting the wolves. The human hunters shot or poisoned every wolf in northern Arizona. Remove the wolf cut-out. Ask: With the wolves gone, what do you think happened to the number of deer? (Their numbers increased.) Tell the students that with no wolf predators, many more deer survived and the deer population grew and grew. Add four more deer cut-outs to the row on the board. Tell the students that population explosion is a way to describe the number of deer. Ask: What did the deer eat? (twigs and leaves from trees) Did the number of grown-up trees increase quickly? (no) Point out that trees grow slowly. The deer's food supply stayed the same, but the number of animals depending on it increased. Tell the students that the deer were so hungry that they began eating young trees that couldn't survive the nibbling. Those trees died. Before long, the forest had fewer trees. Remove some of the tree cut-outs. Ask: What do you think happened to the deer when their food supply dwindled? (They starved.) Tell the students that many of the deer died because there was not enough to eat. Remove all but two deer cut-outs.
Ask: What was the result of killing all the wolves? (At first there were more deer, but then there were fewer trees and fewer deer.) Tell the students that the people who killed all the wolves did not understand that the web of life connects animals and plants together. What happens to wolves affects what happens to deer, trees and any other plants and animals in their food web.
Tell the students that scientists who study the connections between plants and animals in a community are called ecologists. Write this word on the board. Tell the students that what they have been learning about--how living things interact with their environments--is called ecology. Write this word on the board, too. Tell the students that ecologists study all kinds of natural communities. Some ecologists look for connections between the plants and animals that live in ponds, some study forest communities or desert communities, or the living things in streams or tropical rainforests, in the oceans, in caves, on mountaintops, underground or the living things in cities. As you mention these communities to the students, point to them on the board. Tell the students there are living things in communities all over the planet. Some communities are very, very small. For instance, there is a community of very tiny living things in the stomach of a termite! Ecologists call these communities that they study ecosystems. Write this on the board also. Tell the students that ecologists are like detectives. They investigate what part each animal and plant plays in the ecosystem and how it is connected to others in the web of life.
As a writing opportunity, have the students write paragraphs to answer these questions: If you were an ecologist studying the web of life, what community or ecosystem would you want to study and why? What kinds of plants and animals might you find in that ecosystem? Describe what equipment you might take on your ecological expedition. Refer the students to the list of communities on the board for ideas. Some paragraphs will undoubtedly focus on adventures the young ecologists have studying an ecosystem. If you want to offer a sample paragraph to your students:
 

I would like to be a desert ecologist because I want to learn more about rattlesnakes and how they are connected to a desert food web. I'm going to watch rattlesnakes and find out what kinds of animals they eat. The desert is a hot, dry place, so I'm going fill my jeep with lots of water containers and a tent for shade. I will also take tall boots. If I accidentally get too near a rattlesnake, it won't be able to bite my ankle. The desert is full of cactus and scorpions.

If there is time, have the students share their paragraphs.
Ask: If you were an ecologist studying ecosystems in northern Arizona, what advice would you have given the people that wanted to kill all the wolves? (Don't shoot the wolves. They are an important strand in the web of life.) Remind the students that when wolves were wiped out in Northern Arizona, the ecosystem went out of balance--it wobbled.

Additional Activity
If available, read Wolf Island by Celia Godkin aloud. Ask: What animals were affected by the disappearance of wolves from the island? Put a wolf cut-out on the board and draw lines to the name of each animal affected.

Long Term Project
Explain to the students that people in the western U.S. killed so many wolves during the past one hundred years that now gray wolves are endangered. Endangered means that a plant or animal is in danger of becoming extinct because there are so few of them left. Remind the students that when a plant or animal becomes extinct, it disappears from the Earth forever. Tell the students that during the next few weeks they will be learning about some of the reasons animals and plants are becoming endangered. These reasons include losing their habitats, pollution and acid rain, oil spills and, as with the wolves, over-hunting. Distribute a list of endangered animals to the students (see attached). Tell the students that to complete part two of their long term project, they should pick an animal from the list about which they are interested in learning more. Tell the students to go to the library and find at least two books with information about the animal they have chosen. Students may find books by looking up the name of an animal in the library's catalog, but are more likely to find information by looking under "endangered" or under the name of the animal's habitat such as "desert animals" or "wetlands." Articles from National Wildlife Magazine or Ranger Rick can also provide information.

Third Grade - Science - Lesson 9 - Ecology

Objectives
Review the basic needs of all animals.
Describe connections between animals and a saguaro cactus in a desert ecosystem and recognize the importance of a single species to the health of an ecosystem.
Create an advertisement to persuade desert animals that a saguaro cactus meets their habitat needs.

Suggested Books
Arnold, Caroline. A Walk in the Desert. New York: Silver Press, 1991.
Baker, Lucy. Life in the Desert. New York: World Book, 1997.
Bash, Barbara. Desert Giant. Boston: Little Brown, 1989. This Reading Rainbow selection is a compelling example of plant and animal interdependence. It is a popular book in ecology units throughout the U.S.
Baylor, Byrd. Desert Voices. New York: Atheneum, 1981.Ten desert creatures describe their lives.
Cobb, Vicki. This Place Is Dry. New York: Walker, 1989. In addition to plants and animals, this book includes the people that live in the Sonoran Desert and how they have coped with the environment.
Gibbons, Gail. Deserts. New York: Holiday House, 1996. As in all Gibbons' books, the illustrations of desert landscapes and creatures are outstanding. She concentrates on the ecosystem of the Sonoran desert, but also includes creatures that live in other deserts of the world. Includes a world map showing deserts.
Gise, Joanne. A Picture Book of Desert Animals. Mahwah, NJ: Troll, 1991.
Guiberson, Brenda. Cactus Hotel. New York: Holt, 1991. Features the life cycle of a two- hundred-year-old saguaro cactus and the many animals that use it for food and shelter.
Yolen, Jane. Welcome to the Sea of Sand. New York: Putnam, 1996. A lyrical description of the sights and sounds of the Sonoran Desert of Arizona.
Simon, Seymour. Deserts. New York: Morrow, 1990.
Wallace, Marianne. America's Deserts: Guide to Plants and Animals. Golden, CO: Fulcrum, 1996. Includes a desertscape illustration for each American desert showing the plants and animal inhabitants of each. Did you know sea turtles visit the Sonoran Desert?

Teacher Resource
Churchman, Deborah. "Night in the Sonoran Desert."Ranger Rick Magazine, February, 1997.

Procedure
Review with the students the definition of an ecosystem: a community of living things and their environment. Remind them that animals and plants in an ecosystem are interconnected; they depend on each other. Remind the students that they have learned about food webs and how producers, consumers and decomposers depend on each other for food. Tell the students that plants and animals also depend on each other for other things they need to survive. Ask: What do all animals need to survive? (food, water, shelter, and a place to breed and raise young) List these on the board. Tell the students that today they will learn about a special plant that grows in a very harsh environment--the desert. This plant provides many desert animals with what they need to survive. Tell the students that this special plant, the saguaro (sa-WAHR-oh) cactus, provides animals in its environment with food, water, shelter and a place to breed and raise young.
Ask: What do you think makes a place a desert? (very little rainfall) Tell the students that a dry climate is part of the desert ecosystem. Daytime in many deserts is so hot that any moisture evaporates quickly. Plants and animals in the desert have adapted to the lack of water.
Ask the students to imagine that through magical means, a giant bird has snatched them up in its claws and flown them to a desert in southern Arizona. Plop! The bird has set them down on a broad desert plain. Say: It is high noon and hotter than blazes in the desert. You have only a piece of chewing gum in your pocket. How will you survive? (Accept all answers. It is important that the students visualize themselves in this harsh environment.)
Tell the students that the number one rule for desert creatures is: Get out of the sun! Write this on the board. Tell the students that all around them in the desert, animals are hiding from the hot sun. Spadefoot toads have burrowed underground. Packrats have built spiny nests where they curl up in the shade. Rattlesnakes coil under rock ledges. Wild pigs have buried themselves in the sand. Elf owls, coyotes and scorpions come out only at night when it is much cooler. Ask the students if they agree that shelter is very, very important to survival in the desert.
Show the students the cover of either Cactus Hotel by Brenda Guiberson or Desert Giant by Barbara Bash. Tell them that the book you are going to read to them describes the life cycle of this desert plant, the saguaro cactus. Saguaros can live nearly two hundred years. Write a subtraction problem on the board: 1997-200 years'. Ask a student to solve it. Point out to the students that some saguaro cacti that are alive today sprouted in 1797 when the president of the U.S. was George Washington. Ask the students to listen carefully as you read because when you have finished, you are going to ask them to tell you about the animals that depend on the saguaro for food, shelter or a place to breed and raise young. Read aloud one of the books. Cactus Hotel requires at least five minutes to read; Desert Giant requires at lease seven minutes of reading time.
When you are finished reading, tell the students that you want to make a web on the board that shows the connections between plants and animals in the desert ecosystem portrayed in the book. Draw a large shape of the saguaro in the middle of the board. Ask: what animal was the first to make a shelter in the saguaro? (gila woodpecker) Show the students the illustration from the book if they cannot remember. Ask: What did the woodpecker use the shelter for? (To hatch and raise its babies) Draw a small hole in the saguaro and a line pointing to it. Write woodpecker at the other end of the line and under it raise babies. Ask: What other birds used the cactus for nesting? [Answers to following questions will vary according to which book was read] (Dove or hawk built nests on its arms) Draw a line from one of the arms and write dove or hawk at the end of the line and raise babies under that. Ask: What animals depended on the old woodpecker holes for shelter? (elf owls-shelter, bats-shelter, pack rats-raise babies) Draw a line to woodpecker and at the other end list the animals. Tell the students that without the woodpecker to make the holes with its sharp beak, these animals would not have a home in the cactus.
Ask: What animals depended on the cactus for nectar? (birds, bees, butterflies and bats) Draw a small flower on the cactus shape. From the flower draw a line. At the end of the line write birds, bees, bats and under that write food. Remind the students that the birds, bees and bats that fed on the nectar also pollinated the flowers so fruit would grow. Ask: What animals ate the fruit of the cactus? (packrats, birds, ants, coyote, javalina, people) Draw a fruit shape on the cactus shape. Draw a line from it and on the other end write the animals' names (including people) and under them write food. Remind the students that the animals that ate the fruit also helped spread the cactus seeds inside the fruit so more cactus would grow. Ask: After the very old cactus fell to the ground, what animals found shelter inside its ribs? (ants, termites, scorpions, spiders, lizards, snakes, mouse) Write these animals' names on the board and write shelter beneath them. Draw a line from them to the middle of the cactus. Ask the students to take a look at all the animals that depend on the food, shelter and space to raise babies that this cactus hotel provides. Ask: Do you think the saguaro cactus is an important part of the desert ecosystem? (yes) Erase the cactus outline. Ask: What do you think would happen if the saguaro cactus disappeared? (Many animals would not survive.)
Ask the students to pretend that desert animals can read. Tell the students that you want them to write an advertisement for a room in the saguaro cactus hotel. Ask them to try to persuade a bat, packrat, bird or insect that a saguaro cactus is the best place to live. How does the cactus fill their needs? Ask: What do advertisements do? (try to persuade a person to buy a product by telling how it will help the buyer ) Ask: What is the product you are trying to sell in this advertisement? (a room in the cactus hotel) Ask the students to create persuasive advertisements that sell the product to the animal they are trying to convince. Think about what that animal would want in a home.

Long Term Project
Check to see that each student has correctly addressed an envelope and has found two books or sources of information about an animal. For homework, ask the students to answer in full sentences the questions on the checklist sheet about the endangered animal they have chosen. Remind them that they are to locate the area of the world where the animal lives on a world map.

Third Grade - Science - Lesson 10 - Ecology
Candle and chalk activities adapted from Pollution and Waste by Sally Morgan and Rosie Harlow

Objectives
Identify sources of air pollution.
Suggest ways to reduce air pollution and conserve energy.
Describe the cause and some damaging effects of acid rain.

Materials
Candle in a holder, matches, heatproof dish
Bottle of white vinegar, clear glass dish or shallow bowl, a piece of chalk

Suggested Books
Bailey, Donna. What We Can Do About Noise and Fumes. New York: Franklin Watts, 1991. Deals with causes for smog worldwide, how acid rain is produced and also with the effects of noise pollution on people and animals.
Bright, M. Acid Rain. New York: Gloucester Press, 1991. The poisoning effects of acid rain around the world are examined as well as how to identify trees and plants that are dying due to acid rain.
Earthworks Group. 50 Simple Things Kids Can Do to Save the Earth. New York: Andrews and McMeel, 1990.
Geisel, Theodor Suess. The Lorax. New York: Random House, 1971.
Hare, Tony. Polluting The Air. New York: Gloucester Press, 1992.
Harlow, Rosie and Sally Morgan. Pollution and Waste. New York: Kingfisher, 1995. This outstanding book gives a brief overview of major pollution problems and includes simple activities to demonstrate larger, much more complicated principles.
Jeffers, Susan. Brother Eagle, Sister Sky. New York: Dial, 1991. This Parents' Choice Award winner offers the speech given by Chief Seattle over a hundred years ago about the sacredness of our relationship with the Earth. Beautifully illustrated.
Teacher Resources
Roest, Michele. Animals Tracks Activity Guide. Washington, D.C.: National Wildlife Federation, 1995. Contains projects, activity sheets and lesson plans for elementary grades on air and water quality, recycling, endangered species and energy conservation.

Teacher Note
Chief Seattle's speech was made in 1854. The translator and subsequent anthologists took liberties with his actual words. The quote used in this lesson is from a version published in 1970.

Procedure
Remind the students that last time they learned how just one kind of plant can be very important to the survival of animals in its ecosystem. Ask: What desert plant provides habitat and food for other animals? (saguaro cactus) Point out that the saguaro cactus is a part of the web of life in the desert ecosystem. If the cactus were taken out of the desert web of life, an important strand in the web would be broken. Animals that depend on the cactus would not have what they need to survive.
Tell the students that they have learned about what animals need to survive. Ask: What do people need to survive? Write the students' responses on the board. The list should include air, water, food, shelter, space and love (infants need caring or nurturing). Ask the students to think about their place in the web of life as you read them something once said by a Native American named Chief Seattle. Read the following quote:
"Whatever befalls the earth, befalls the sons of the earth. Man did not weave the web of life; he is merely a strand in it. Whatever he does to the web, he does to himself..."
Ask: Are people part of the web of life? (yes) What do you think Chief Seattle meant when he said, "Whatever [man] does to the web, he does to himself."? (Accept all answers.)
Write the word pollution on the board. Tell the students that pollution means something harmful in the environment that does not belong. Tell them that today they are going to find out where air pollution comes from and come up with some ideas of their own to clean up the air.
Tell the students that dirty air is polluted with two kinds of pollution--particles and gases. We can sometimes see the particles as smoke or soot, but the gases are invisible. Ask: Where do these pollutants come from? (Car, truck and bus exhaust, factory smoke stacks, power plants that burn fuel and make smoke and soot, etc.) List sources of air pollution on the board. Tell the students that the engines in cars, trucks and buses burn gasoline. When fuels are burned, gases and particles go into the air. Factories that make products and power plants that make electricity burn fuels, too and release pollution into the air. Incinerators that burn garbage also release soot and gases into the air.
Light a candle and tell the students that wax is the fuel for this fire but gasoline, coal, oil and wood are burned to make energy for people. Carefully hold a heat-proof dish upside down over the yellow part of the flame for 30 seconds. Move the dish from side-to-side to spread the black carbon deposit. Show the students the carbon stain and tell them that usually this soot you have captured would have escaped into the air. Tell them the invisible gases from the burning wax candle are now in the air. Blow out the candle and point out the visible smoke also escaping into the air. Ask the students to imagine the number of cars in Baltimore City burning gasoline at this very moment. We might be able to see smoky exhaust coming out of the tailpipes of those cars, but most of the pollution is invisible, like the invisible gases from the candle. Ask the students to imagine all the lights, fans, heaters, air conditioners, refrigerators, T.V.s, washers and dryers, water heaters, toasters and other appliances in Baltimore that need electricity to work. With all the homes and businesses in Baltimore that need electricity, imagine how much fuel the Baltimore Gas and Electric Company must burn to make that energy. Burning fuels makes pollution.
Tell the students that really dirty air is called smog. It can make the sky look brown. Dirty air can smell bad, too. Gases from burning coal or oil can smell like rotten eggs. Ask: Do you think breathing dirty air is good for people? (no) Do you think it is healthy for plants and animals? (no) Do you think polluted air should be part of our city habitats and ecosystems? On the board write Problem: Burning fuels ' air pollution. Point out the list of pollution sources on the board. Ask: What can people do to reduce the amount of air pollution in our city? (Accept all answers.) Write the students' responses on the board. Some suggestions might include: Reduce the number of cars in the city. Have more people use the Metro, Light Rail, buses or bicycles instead of so many individual cars. One radical suggestion might be to ban cars in the city. Have all people use public transportation or bikes. Don't burn garbage in incinerators. Reduce the amount of electricity we use so power plants don't have to burn so much fuel. Discuss with the students ways they might be able to reduce the amount of electricity they use at home, for instance, turning off lights and/or T.V. when they are the last to leave a room or not keeping the refrigerator door open longer than necessary. Planting and tending trees in empty lots and city streets can offer shade and reduce the need for fans and air conditioning. A student might suggest making electricity another way, without burning fuels. If so, you might want to discuss clean, renewable forms of power such as solar energy or wind power. Another suggestion might be that cars and buses be powered by something other than gasoline engines (electric or solar-powered).
After you have discussed ways to reduce air pollution in Baltimore, tell the students that there is another problem about air pollution--it travels. Air currents carry air pollution made by car exhaust and power plants in other parts of the country to our air space adding more pollution to our pollution. To clean up the air, every city has to do its part because we are all connected by air space--our atmosphere.
Write the words acid rain on the board. Tell the students that there is something called acid rain that forms when two gases made by burning fuels mix together high up in rain clouds. The clouds travel and then drop acid rain on the land below. Acid rain can do a lot of damage. Trees and plants soak up the rain and then slowly die. Acid rain collects in rivers and lakes killing fish and plants. It runs down stone statues and buildings and dissolves the stone.
Show the students a piece of chalk. Tell them that chalk is made of a kind of soft stone. Show them the bottle of vinegar and explain that vinegar is acidic like acid rain but is a stronger acid. Pour some of the vinegar into the glass dish. Ask: What do you think will happen when I put this chalk made of soft stone into this strong acidic vinegar? (Accept all answers.) Drop the chalk into the vinegar. In a few moments, remove what is left of the chalk from the vinegar. Ask: What happened to the chalk? (It is dissolved or eaten away by the acid in the vinegar.) Tell the students that acid rain is a weaker acid than vinegar and so would take more time to eat away the stone on buildings. Tell them that acid rain has destroyed acres and acres of forests in North America and in Europe and has caused the deaths of lake, river and stream ecosystems.
Remind the students that they learned how an animal's or plant's survival depends on the health and balance of its ecosystem. Ask: Do you think people's health and survival depends on the health of our ecosystem, too? Ask the students to listen again to the words of Chief Seattle: "Whatever befalls the earth, befalls the sons of the earth. Man did not weave the web of life; he is merely a strand in it. Whatever he does to the web, he does to himself..."

Long Term Project
Ask several students to identify the endangered animal they have chosen and locate where it lives on the world map. Have them read what they have written about their chosen endangered animals.

Third Grade - Science - Lesson 11 - Ecology

Objectives
Simulate sources of pollution in a model mountain lake.
Describe three ways to limit pollution of the Chesapeake Bay.

Materials
Picture of a mountain lake from a book or magazine
A large, clear glass bowl full of water
Nine simulated pollutants in labeled paper cups: DIRT-a few tablespoons of soil; TRASH- gum or candy wrapper; PAINT-small amount of water with a drop of red food coloring; GAS AND OIL-small amount vegetable oil; SEWAGE-teaspoon of soy sauce; FERTILIZER- small amount of water with a drop of blue food coloring; PESTICIDE-1/4 cup vinegar; ASHES-baking soda; CLEANERS-one drop of liquid detergent in small amount of water

Suggested Books
Berger, Melvin. Oil Spill! New York: HarperCollins, 1994. This book, one in the Let's-Read- and-Find-Out Science series, tackles a difficult subject very successfully. The various methods of oil spill clean-up are outlined as well as sections on energy conservation and what children can do to prevent oil spills.
Carr, Terry. Spill! The Story of the Exxon Valdez. New York: Franklin Watts, 1991.
How do you rescue hundreds of birds and sea otters from the devastating effects of an oil spill? How do you clean up the damage caused by a spill that coated 1,000 miles of shoreline in breath-takingly beautiful Prince William Sound with greasy, black oil? This book examines the cause of the spill, its effects on nature, attitudes and the law, and what it is teaching scientists about the limits of nature's resilience.
Coombs, Karen Mueller. Flush! Treating Wastewater. Minneapolis: Carolrhoda, 1995. An unusually appealing book considering its focus: the history of sewage and what happens when we flush. Waste water treatment is a large part of the country's efforts to clean up streams and rivers.
Patten, J.M. Oil Spills. Vero Beach, FL: Rourke, 1995. Highlights the uses of oil not only as a fuel, but also in manufacture of medications and in production of plastics and clothing. In an oil spill, however, oil is a threat, "Greasy, green-black oil stays on top of the water, and the winds and tides spread it around."
Stille, Darlene. Water Pollution. Chicago: Childrens Press, 1990.Contains a succinct explanation of how fertilizer and sewage pollution can cause oxygen depletion in lakes.

Procedure
Remind the students that last time they learned how burning fuels, such as gasoline, coal and oil, cause air pollution. Tell the students that today they will be learning how water gets polluted and what can be done to keep it clean. Show the students a picture of a mountain lake from a book or magazine. Tell them that this is a lake you are going to call Big Bear Lake and they are going to help you tell the story of how Big Bear Lake became polluted.
Show the students the large glass bowl full of clean water. Ask them to imagine that this bowl of crystal clear mountain water is Big Bear Lake. Big Bear Lake is filled by many streams that tumble down the surrounding mountainsides in beautiful waterfalls and pour their clear, cold waters into the lake. The lake is home to many animals. Ask the students what animals they'd like to imagine living in and around Big Bear Lake (examples: fish, turtles, ducks, water snakes, snails, frogs, bear, deer, moose, wolves).
Tell the students that one day some people came in a car to the shores of Big Bear Lake. "This is the perfect place to build a hotel and restaurant," said one man. "We'll call it Big Bear Lodge."
"And we can build a pier out into the lake and make a marina for motor boats," said another man. "But first we should knock down some of this forest and build a wide road so people can get to Big Bear Lodge. Bring in the bulldozers!"
When the bulldozers dug up the ground, a lot of dirt was washed into the lake. Have a student put DIRT into the lake to simulate the erosion from construction. Once the road was built, the men started on the hotel and restaurant. The workmen liked to eat their lunches next to the lake. They usually threw their trash into the water. Have a student throw TRASH into the bowl to simulate trash. When the painters finished painting the rooms in the hotel, they cleaned their painting equipment in the lake. Have a student put PAINT into the water.
When the hotel was finished, people came to the lake to swim and boat and fish. They brought their motor boats and enjoyed speeding around the lake. Many of their boats leaked gasoline and oil into the lake. Have a student add GAS AND OIL to the lake. Meanwhile, each time the guests in the hotel flushed their toilets, the water went into an underground septic system. Unfortunately, the builders did not put in a very good septic system. Soon it began to leak and sewage began to seep into the lake's waters. Have a student pour SEWAGE into the lake.
On a hillside near the lake, one of the owners of the hotel decided to plant a vineyard and grow grapes. He cleared the land and planted his vines. He also spread fertilizer on his land. When it rained, the fertilizer washed into the lake. Have a student add FERTILIZER to the lake. The hotel owner also decided to spray his grape vines with chemical pesticides to kill the bugs that might eat his plants. The pesticides washed into the lake, too. Have a student add PESTICIDES to the bowl.
The hotel owners and staff found it was much easier to burn the big piles of trash from their guests than to drive it out to a dump, so they burned it and then dumped the ashes into the lake. Have a student dump ASHES in the lake. Meanwhile, boat owners did not like the oily water of the lake messing up their boats, so they washed the boat decks with detergent and other cleaners and rinsed the suds into the lake. Have a student add a CLEANERS to the lake.
Ask: What has happened to crystal clear Big Bear Lake? Is this a healthy ecosystem? (No, the lake is polluted.) Would you want to swim or fish in this lake? (no) What do you think has happened to the animals that were living in and around the lake? (Many of them are probably dead from the poisonous pollution or have moved away.) Ask: Do you think the poisons from the pollution in the lake are in the food chain? Do you think any fish caught in the lake might have poison in them? What might happen to any animals or people that eat the fish? (Poisons from the fish would be passed on to those that ate them.) Ask: Did the people pollute the lake on purpose? Discuss the fact that the people were probably unaware that what they were doing was polluting the Big Bear Lake.
Tell the students that many of the things that polluted the lake are the same things that are polluting the Chesapeake Bay. Review the labels on the cups of pollutants. Point out that people around our Chesapeake Bay are more aware of what causes pollution in the Bay. They know that building on the shoreline will cause lots of soil to wash into the Bay. Now there are laws that limit building on the shoreline. Tell the students that waste water treatment plants filter and treat Baltimore's sewage until it is nearly clean before releasing it into the rivers that feed the Bay. Dumping garbage or chemicals from factories into the Bay is against the law.
Tell the students that a big problem in cleaning up the Bay's waters is a pollutant that comes from miles and miles away. Pick up the cup labeled FERTILIZER. Explain to the students that like the fertilizers that washed down into the lake from the hillside vineyard, fertilizers on farm fields here in Maryland and way up in Pennsylvania wash down streams and rivers and into the Bay every time it rains. There is one kind of tiny plant in the Bay that thrives on all that fertilizer. Floating, green, slimy algae uses the fertilizer to grow and grow and grow. It blocks out the sunlight to plants and animals below. Then as it dies and decays, it uses up oxygen in the water so there isn't enough for fish to breathe. Ask: What do you think happens to the food web in the Bay when algae takes over? (fewer fish, not enough for fish eaters to eat) Tell the students that to protect the Bay, we have to find a way to keep fertilizer out of the water.
Write Clean Up the Bay on the board and ask the students to help you list three ways to protect the Chesapeake Bay. (Don't build on the shoreline. Keep fertilizer from washing into the Bay. Don't dump garbage or chemicals into the Bay.)

Long Term Project
Have another group of students identify the endangered animals they have chosen, show where they live on a world map and read what they have written about them. Tell the students that you will be collecting their write-ups to include in a class book on Endangered Species.

Third Grade - Science - Lesson 12 - Ecology

Objectives
Describe some reasons why animals become endangered.
Identify some endangered species.
Recognize how laws can protect endangered species.

Materials
Pictures of a bald eagle, a box turtle and manatees from Suggested Books
U.S. map showing the east coast

Suggested Books
Amato, Carol. Chessie: The Meandering Manatee. New York: Barrons Juv., 1997. This brand new book tells the story of Chessie, the manatee that wandered north and into the Chesapeake Bay. People in Maryland and Florida, concerned for Chessie's well being, banded together to track the manatee and be sure he returned to warmer waters before winter.
Berger, Melvin. Look Out for Turtles! New York: HarperCollins, 1997. Illustrations of all types of turtles.
Burton, Robert. Wildlife in Danger. Morristown, NJ: Silver Burdett, 1993.
Clark, Margaret Goff. The Vanishing Manatee. New York: Cobblehill, 1990. Examines environmental pressures on this gentle animal and the efforts to save the species.
Darling, Kathy. Manatee. New York: Lothrop, 1990.
Facklam, Margery. And Then There Was One. Boston: Little Brown, 1990. Explores the reasons species become extinct and offers some success stories concerning conservation efforts.
Few, Roger. Macmillan's Children's Guide to Endangered Animals. New York: Macmillan, 1993.
George, Jean Craighead. The Case of the Missing Cutthroats: An Ecological Mystery. New York: Harpercrest, 1996. A girl named Spinner catches a cutthroat trout in the Snake River, a river where the trout was thought to be extinct. How did it get there? How did it survive? That is the mystery Spinner sets out to investigate.
Harman, Amanda. Manatees and Dugongs. New York: Benchmark, 1997. Describes the habitat and behavior of these aquatic mammals.
Herschell, Michael. Animals In Danger. Austin: Steck-Vaughn, 1995.
Hirschi, Ron. Turtle's Day. New York: Cobblehill, 1994. Includes color photos of the eastern box turtle.
Irvine, Georgeanne. Protecting Endangered Species at the San Diego Zoo. New York: Simon Schuster, 1990 . Examines what zoos do with captive breeding programs to preserve species. Includes sections on cloud leopards and mhorr gazelles.
Jacobs, Francine. Sam the Sea Cow. New York: Walker, 1991. Follows the lifestyle of Sam, a baby manatee, from birth to the moment he leaves his mother.
Jenkins, Priscilla Belz. Falcons Nest on Skyscrapers. New York: HarperCollins, 1996. The endangered peregrine falcons featured in this Let's-Read-And-Find-Out-About-Science book nest on a building in Baltimore's Inner Harbor. They are being monitored by employees of USF&G. Includes views of the National Aquarium and the Baltimore skyline.
Kratt, Chris. Creatures in Crisis. Scholastic, 1997. This paperback on endangered animals comes from the host of the popular PBS show, Kratt's Creatures.
Lauber, Patricia. Alligators: A Success Story. New York: Holt, 1993. A declining species is saved from extinction.
Pollack, Steve. Atlas of Endangered Animals. New York: Facts On File, 1993. Excellent illustrations of endangered animals and short useful text.
Sibbald, Jean. The Manatee. Minneapolis: Dillon, 1990. Describes the manatee's relationship to humans--those that unintentionally hurt it and those that are trying to help it survive.
Silverstein, Alvin. The Manatee. Brookfield, CT: Millbrook, 1995.
________. Saving Endangered Animals. Hillside, NJ: Enslow, 1993. Focuses on various conservation efforts to preserve biodiversity around the world.
Stone, Lynn. Endangered Species. Chicago: Childrens Press, 1984.
Tesar, Jenny. Endangered Habitats. New York: Facts on File, 1992.
Wright, Alexandra. Will We Miss Them? New York: Charlesbridge, 1993. Told through the eyes of an eleven-year-old, this book looks at several endangered species and efforts to protect them.

Teacher Resources
Naturescope: Endangered Species: Wild and Rare. Washington, D.C.: National Wildlife Federation, 1989. Includes copycat pages and activities plus information on the giant panda, black rhino and sea turtles.
National Wildlife Federation for Kids Website (http://www.nwf.org/kids/). Includes a section on endangered species which includes following text: "As humans take up more and more space on the planet, we destroy the habitats of other plants and animals. This is the biggest reason why animals are becoming extinct. Plant and animal species are disappearing at least 1,000 times faster that any other time in the last 65 million years." Also includes activities, puzzles and a list of ways kids can help protect endangered species.

Procedure
Ask the students to take out their lists of endangered animals. Ask: What does endangered mean? (Endangered means that a plant or animal is in danger of becoming extinct.) Remind the students again that when a plant or animal becomes extinct, it disappears from the Earth forever. Ask: What are some reasons that plants and animals become endangered? (pollution, over-hunting or over-collecting, loss of their habitats) Write these reasons on the board.
Discuss examples of pollution's effects on animals. Remind the children that they learned about Rachel Carson in first grade. She wrote a book called Silent Spring in which she warned people that pollution from the insecticide DDT had entered the food chain. DDT was sprayed on lawns, fields and trees to kill insects. Review how poison moved through the food chain from the birds and fish that ate the poisoned insects to the animals that ate the birds and fish. Tell the students that bald eagles are birds at the top of the food chain. Show the students pictures of a bald eagle. Remind the students that the bald eagle is our national symbol and is on both dollar bills and quarters, yet the bald eagle was on the list of endangered species--in danger of extinction--because of DDT pollution. Explain that DDT collected in the eagles' bodies from eating poisoned fish and caused the eggs they laid to have weak shells. The eggs broke before the babies could hatch. Fewer bald eagles survived and before long, these birds were endangered.
Remind the students that when the use of DDT was forbidden in the U.S., bald eagles eventually began laying healthy eggs again. Today the bald eagle is no longer on the endangered species list.
Ask the students to look at the list of endangered species. Tell the students that while bald eagles are no longer on the list, other plants and animals are being added all the time. Point to the second reason on the board--over-hunting. Ask: What animal did we talk about earlier that was over-hunted? (gray wolf) Tell the students that other animals endangered by over-hunting are rhinos and elephants hunted for their horns or ivory tusks which can be sold for lots of money. Polar bears and alligators were once over-hunted, too. People wanted polar bear fur and alligator skin shoes and handbags. Laws were passed to protect these animals and now the numbers of polar bears and alligators have increased.
Tell them that there is an animal that was common in Maryland when their parents were little. Today there are so few of them that it is difficult to find a single one. The name of the animal is a box turtle. Show the students a picture of a box turtle from Suggested Books. Tell the students that the reason there are fewer box turtles in the woods and fields and parks is because people in other countries wanted them for pets. Turtle hunters collected as many box turtles as they could find and shipped them to pet stores in places like Japan where people bought them to keep as pets. Now it is against the law to collect box turtles from the wild.
Explain to the students that a very important law called the Endangered Species Act was written to protect animals from extinction. Write Endangered Species Act on the board. Tell the students that species means kind or type of plant or animal. Some people have called the Endangered Species Act a bill of rights for all living creatures. The idea behind the law is that since all living things are connected and dependent on one another, we need them all to keep our ecosystems balanced and healthy. We should work hard to protect species of plants and animals and not cause their extinctions. Even a tiny creature can play a big part in keeping our environment healthy.
Point to the third reason on the board--loss of habitat. Ask: How does an animal lose its habitat? (The leading cause of habitat destruction is people changing the environment--clearing land, filling in wetlands, building roads, buildings, parking lots, etc.) Ask: What can an animal do when its habitat is destroyed? (go somewhere else) What if there isn't any more habitat to go to? Tell the students that habitat destruction can push animals out and cause them to become endangered.
Tell the students that a few years ago an endangered animal from Florida swam all the way to Maryland and up into the Chesapeake Bay. People were very surprised to see this endangered animal. They nicknamed him Chessie. Show the students pictures of manatees from Suggested Books. Tell them that Chessie is a manatee, sometimes called a sea cow. Manatees are gentle creatures that live in shallow, warm, tropical waters and munch on underwater sea grasses. They are mammals and breathe air but can hold their breaths under water for long periods of time to eat. A manatee can grow to be 1,000 pounds! Tell the students that in olden times, sailors told stories about mermaids, creatures who were half woman and half fish. Some people think that what they were seeing from a distance were really manatees. Discuss how a manatee may or may not look like a mermaid. Tell the students that Marylanders worked with the Save the Manatee Club in Florida to help get Chessie back home before cold weather might have killed him. Show the students on a U.S. map Chessie's habitat (the coastal waters of Florida) and his possible route to the Chesapeake Bay.
Tell the students that people in Florida are very concerned about protecting the endangered manatees. Manatees have to share the coastal waters of Florida with lots and lots of boaters. A big danger to manatees are motor boats and boat propellers. Manatees are injured and sometimes killed by boats that run over them and cut them. Ask: If you wanted to protect the manatees from boat injuries, what would you do? (Accept all answers. Possible responses might be: keep boats out of areas where manatees feed; let people know about the problem so they can be more careful; put guards around the propellers so they don't hurt the manatees.)
Ask the students to make a poster telling boaters about manatees and what they can do to help protect this endangered species.

Long Term Report
Remind the students that they should be working on the letters they will be sending to their representative or senator. Review the content of the letter and the correct format for a letter.
 

Third Grade - Science - Lesson 13 - Ecology

Objectives
Recognize the difference one man, John Muir, made in preserving wilderness through the power of his writing.
Identify some national parks.

Materials
Picture of John Muir from Suggested Books
Classroom-size U.S. map
Pictures of land and animals in some national parks from Suggested Books or from magazines such as Audubon, National Wildlife, National Geographic or from literature distributed by the National Park Service

Suggested Books
Brower, Kenneth. Yosemite: An American Treasure. Washington, DC: National Geographic, 1990. Full of color photos of the park.
Faber, Doris and Harold Faber. Nature and the Environment: Great Lives. New York: Scribners, 1991. Includes descriptions of some of Muir's most memorable inventions such as the tipping bed to get a person up in the morning and the automatic book opener.
Force, Eden. John Muir. Englewood Cliffs, NJ: Silver Burdett, 1990. An excellent, well-written biography that explores Muir's contribution to the conservation movement as well as his relationships with his family and friends. Muir's ability to overcome his dreadful childhood and abusive father and to keep his open-hearted nature are inspirational.
Greene, Carol. John Muir: Man of the Wild Places. Chicago: Childrens Press, 1991. This Rookie Reader is short, informative and full of illustrations and photos.
Kent, Deborah. Yellowstone National Park. Chicago: Childrens Press, 1994.
Muench, David. Discover America: The Smithsonian Book of the National Parks. Washington, DC: Smithsonian, 1995.
Naden, Corinne and Rose Blue. John Muir: Saving the Wilderness. New York: Millbrook, 1990.
Patent, Dorothy Hinshaw. Places of Refuge: Our National Wildlife Refuge System. New York: Clarion, 1992. Discusses ways nature's equilibrium is maintained in wildlife refuges. Includes many wildlife photos.
Petersen, David. Grand Canyon National Park. Chicago: Childrens Press, 1992.
Pick, Christopher. America's National Parks. New York: Crescent, 1993.
Pirie, Donald. National Park Vacations: the West. Boca Raton, FL: Cool Hand Com., 1994.
Young, Donald. The Sierra Club Book of Our National Parks. Boston: Little Brown, 1990. Beautiful photographs document various ecosystems in our national parks.
Teacher Resources
Muir, John. Our National Parks. San Francisco: Sierra Club Books, 1991. These ten essays written for the Atlantic Monthly magazine were first compiled into a book in 1901. Muir's descriptions of his beloved Yosemite inspired many people to support conservation and protect their national parks from exploitation. In the preface he writes: "I have done the best I could to show forth the beauty, grandeur, and all-embracing usefulness of our wild mountain forest reservations and parks, with a view to inciting the people to come and enjoy them, and get them into their hearts, that so at length their preservation and right use might be made sure."
For more information on the life of John Muir, his impact on conservation, pictures, quotes, activities and lesson plans visit the Sierra Club's website and particularly its John Muir Exhibit at http://www.sierraclub.org/john_muir_exhibit.
For a list of national parks with links to pictures, maps and information on each one, visit http://www.yahoo.com/Recreation/Outdoors/Parks/United_States/National_Parks

Procedure
Ask: Has anyone ever taken a very long walk or hike? About how far did you walk--a mile? Several miles? Tell the students that today they will hear about a man who walked thousands of miles. The man's name was John Muir.
Tell the students that wherever he went, John Muir wrote in his journal about his adventures and about the beauty he found in nature. Muir once said, "When we try to pick out anything by itself, we find it hitched to everything else in the universe." Ask: Does this sound like an idea we've learned about in our study of ecology? (web of life--all living things depend on each other) John Muir had this thought more than a hundred years ago.
Tell the students that on the first page of his journal, John Muir wrote his address. On the board write: John Muir, Earth-Planet, Universe. Ask: Is this the way you would expect a person to write his or her address? Erase John Muir and write in one of the students' names. Ask the student if this could be his address. Point out that this could be the address of anyone on Earth. When John Muir wrote this address in the beginning of his journal, he was saying that the whole Earth is his home, just as it is yours and mine.
Show the students a picture of John Muir. Tell the students that John Muir was a wanderer, an inventor, a writer, a mountain climber, a scientist and a lover of the wild places still left in the world. On a 1,000 mile walking trip from the Midwest to the Gulf of Mexico, he wrote this in his journal:
"I drifted from rock to rock, from stream to stream, from grove to grove. Where night found me, there I camped. When I discovered a new plant, I sat down beside it for a minute or a day, to make its acquaintance and hear what it had to tell."
Once, when a big wind storm came up, Muir climbed a tall pine tree and held on tight just to feel what it was like to swing and sway in the wind and to listen to it whistle through the pine branches. Here is what Muir wrote about how energy moves through living things and how nature is ever-changing:
"Nature is ever at work building and pulling down, creating and destroying, keeping everything whirling and flowing, allowing no rest but in rhythmical motion, chasing everything in endless song out of one beautiful form into another."
John Muir's attitude was different from the people of his day. They thought nature was something to be tamed or used for profit. Muir thought wild natural places should be left alone so future generations could enjoy them and discover their beauty the way he had--in every flower, rock and tree and in the grand sweep of the land. But in the 1890s, things began to worry John Muir. He saw lumbermen cutting down huge sequoia trees that had been living for 3,500 years. He saw sheep tearing up the mountain meadows of his favorite place--Yosemite in northern California. People were clearing more and more land for farming and ranching and building towns. To save the wild places, Muir began writing articles for magazines and writing letters to people in Congress describing what these places looked like and urging them to make laws to protect them for all Americans to enjoy. Remind the students that they also are writing to
lawmakers asking them to help protect endangered species. Tell them that this is what Muir wrote in a magazine article:
"Any fool can destroy trees. Trees cannot run away; and if they could, they would still be destroyed--chased and hunted down. It took more than three thousand years to make some of the trees in these Western woods,--trees that are still standing in perfect strength and beauty, waving and singing in the mighty forests of the Sierra. Through all the wonderful, eventful centuries since Christ's time--and long before that--God has cared for these trees, saved them from drought, disease, avalanches,...but He cannot save them from fools,--only Uncle Sam can do that."
Ask: What did Muir mean by "only Uncle Sam can do that?" (only the government can protect the sequoias) Muir convinced Teddy Roosevelt, who was president at the time, to declare the Grand Canyon and Yosemite protected national lands and to make millions of acres of land out west national parkland. People who read Muir's magazine articles, even if they had never seen a forest or a mountain, felt inspired by his writing to work to preserve wild places.
Thanks to John Muir and his writing, some of those wild places were preserved and became our national parks--the Grand Canyon, Yosemite, the Petrified Forest, Sequoia National Park, Yellowstone and 295 other wilderness areas. Show the students pictures of national parks from Suggested Books. Point out that inside our national parks are all types of land and many different kinds of ecosystems--forests, deserts, wetlands, mountains, grasslands, even arctic tundra up in Alaska's Denali National Park. Locate some of these parks on a U.S. map.
Remind the students that had it not been for John Muir, these beautiful natural places would have been cleared for farming or ranching or perhaps become towns or cities. In 1892, Muir founded the Sierra Club, a group of people dedicated to saving wilderness. The Sierra Club today works to educate people about protecting wildlife and preserving habitat. Point out again that loss of habitat is one important reason animals become endangered.

Long Term Project
Have volunteers read the letters they have written to their representatives. Tell the students that you will collect the letters to make copies and will return them so they may be sent in the envelopes the students have already addressed. Show the students the compiled Endangered Species book.

Additional Activities
Take a hike in a woods or park. Tell the students that like John Muir, they will be visiting the rocks, trees, plants and animals that live in the forest habitat and writing about what they see, hear, smell, and touch in a class journal. During the walk, stop often to examine the color and texture of rocks, the smell of leaves, the sound of wind and birdsong. Have the students measure the girth of a tree with their arms (watch out for poison ivy!). If possible, have the class lie down under a tall tree and look up into its branches. Ask for one minute of silence for careful looking and then have the students describe what they see. Have the students note the different habitats offered by the tree (branches, under the bark, underground by the roots). Ask the students to imagine what kind of animals might live in each habitat (nesting birds in the branches or cavity nesters such as woodpeckers or raccoons in the trunk, insects under the bark, chipmunk in burrow under the roots). When back in the classroom, have the students write about their observations. Encourage them to think about how they used all their senses and include descriptions of the way things smelled or felt. Assemble the entries into a class journal with the address on the cover:
_____________'s Class, Earth-Planet, Universe.
 

Read Aloud
Amato, Carol. Chessie: The Meandering Manatee. New York: Barrons Juv., 1997. (0-81209-850-1)
Arnosky, Jim. In the Forest. New York: Lothrop, 1989. (0-688-08162-2)
*Bash, Barbara. Desert Giant. Boston: Little Brown, 1989. (0-316-08307-0)
Baylor, Byrd. Desert Voices. New York: Atheneum, 1981. (0-68416-712-3)
Berger, Melvin. Oil Spill! New York: HarperCollins, 1994. (0-06-022912-8)
Bunting, Eve. Someday a Tree. New York: Clarion, 1993. (0-395-61309-4)
Fleming, Denise. In the Small, Small Pond. New York: Holt, 1993. (0-80502-264-3)
Geisel, Theodor Suess. The Lorax. New York: Random House, 1971. (0-39492-337-5)
*Godkin, Celia. Wolf Island. New York: W.H. Freeman, 1993. (0-71676-513-6)
Greene, Carol. John Muir: Man of the Wild Places. Chicago: Childrens Press, 1991. (0-516-04220-3)
*Guiberson, Brenda. Cactus Hotel. New York: Holt, 1991. (0-80501-333-4)
Guiberson, Brenda. Spoonbill Swamp. New York: Holt, 1992. (0-8050-1583-3)
Jacobs, Francine. Sam the Sea Cow. New York: Walker, 1991. (0-80278-147-0)
Jeffers, Susan. Brother Eagle, Sister Sky. New York: Dial, 1991. (0-80370-969-2)
Jenkins, Priscilla Belz. Falcons Nest on Skyscrapers. New York: HarperCollins, 1996. (0-06021-104-0)
*Lavies, Bianca. Lily Pad Pond. New York: Dutton, 1989. (0-525-44483-1)
*Schwartz, David. The Hidden Life of the Pond. New York: Crown, 1988. (0-51757-060-2)
Williams, Terry Tempest. Between Cattails. New York: Scribners, 1985. (0-684-18309-9)
Yolen, Jane. Welcome to the Sea of Sand. New York: Putnam, 1996. (0-39922-765-2)

Reference
Arnold, Caroline. A Walk in the Desert. New York: Silver Press, 1991. (0-67168-664-X)
Bailey, Donna. What We Can Do About Noise and Fumes. New York: Franklin Watts, 1991.(0-531-11018-4)
Baker, Lucy. Life in the Desert. New York: World Book, 1997. (0-71665-200-5)
Berger, Melvin. Look Out for Turtles! New York: HarperCollins, 1997. (0-06022-540-8)
Bright, M. Acid Rain. New York: Gloucester Press, 1991. (0-531-17303-8)
Brower, Kenneth. Yosemite: An American Treasure. Washington, DC: National Geographic, 1990. (0-87044-794-7)
Burton, Robert. Wildlife in Danger. Morristown, NJ: Silver Burdett, 1993. (0-38206-730-4) Carr, Terry. Spill! The Story of the Exxon Valdez. New York: Franklin Watts, 1991. (0-531-10998-4)
Challand, Helen. Disappearing Wetlands. Chicago: Childrens Press, 1992. (0-516-05511-9) Clark, Margaret Goff. The Vanishing Manatee. New York: Cobblehill, 1990. (O-52565-024-5) Cobb, Vicki. This Place Is Dry. New York: Walker, 1989. (0-80277-400-8)
Coombs, Karen Mueller. Flush! Treating Wastewater. Minneapolis: Carolrhoda, 1995. (0-87614-879-8)
Cortesi, Wendy. Explore a Spooky Swamp. Washington, D.C.: National Geographic, 1978. (0-87044-265-1)
Darling, Kathy. Manatee. New York: Lothrop, 1990. (0-68809-031-1)
Dewey, Jennifer. At the Edge of the Pond. Boston: Little Brown, 1987. (0-31618-208-7)
Downer, Ann. Spring Pool. New York: Franklin Watts, 1992. (0-53111-150-4)
Earthworks Group. 50 Simple Things Kids Can Do to Save the Earth. New York: Andrews and McMeel, 1990. (0-8362-2301-2)
Emory, Jerry. Dirty, Rotten, Dead? New York: Harcourt, 1996. (0-15200-695-8)
Faber, Doris and Harold Faber. Nature and the Environment: Great Lives. New York: Scribners, 1991. (0-684-19047-8)
Facklam, Margery. And Then There Was One. Boston: Little Brown, 1990. (0-31625-984-5)
Few, Roger. Macmillan's Children's Guide to Endangered Animals. New York: Macmillan, 1993. (0-02734-545-9)
Force, Eden. John Muir. Englewood Cliffs, NJ: Silver Burdett, 1990. (0-382-09965-6)
Fowler, Allan. Life in a Pond. Chicago: Childrens Press, 1996. (0-51606-053-8)
George, Jean Craighead. One Day in the Woods. New York: HarperCollins, 1988. (0-690-04724-X)
________. The Case of the Missing Cutthroats: An Ecological Mystery. New York: Harpercrest, 1996. (0-06025-466-1)
________. The Moon of the Alligators. New York: HarperCollins, 1991. (0-06-022427-4)
________. The Moon of the Gray Wolves. New York: Harpercrest, 1991. (0-06022-443-6)
Gibbons, Gail. Deserts. New York: Holiday House, 1996. (0-82341-276-8)
Gise, Joanne. A Picture Book of Desert Animals. Mahwah, NJ: Troll, 1991. (0-81672-148-3) Greenway, Theresa. Swamp Life: A Close-Up Look at the Natural World of a Swamp. New York: Dorling Kindersley, 1993. (1-56458-211-6)
Hansen, Rosanna. Wolves and Coyotes. New York: Grosset, 1981. (0-44847-489-1)
Hare, Tony. Habitats. New York: Macmillan, 1994. (0-02-548155-X)
________. Polluting The Air. New York: Gloucester Press, 1992. (0-531-17346-1)
Harlow, Rosie and Sally Morgan. Pollution and Waste. New York: Kingfisher, 1995. (1-85697614-9)
Harman, Amanda. Manatees and Dugongs. New York: Benchmark, 1997. (0-76140-294-2) Herschell, Michael. Animals In Danger. Austin: Steck-Vaughn, 1995. (0-81145-732-X)
Hester, Nigel. The Living Pond. New York: Franklin Watts, 1990. (0-531-14006-7)
Hirschi, Ron. Turtle's Day. New York: Cobblehill, 1994. (0-52565-172-1)
________.When the Wolves Return. New York: Cobblehill, 1995. (0-52565-144-6)
Hughey, Pat. Scavengers and Decomposers: Nature's Clean Up Crew. New York: Atheneum, 1984. (0-68931-032-3)
Humphrey, Paul. Below the Green Pond. Austin, TX: Raintree/Steck-Vaughn, 1996. (0-81143-745-0)
Irvine, Georgeanne. Protecting Endangered Species at the San Diego Zoo. New York: Simon Schuster, 1990. (0-67168-776-X)
Jackson, Jerome. Nature's Habitats. Washington, D.C.: Starwood Publishing, 1991.(0-912347-78-3)
Kent, Deborah. Yellowstone National Park. Chicago: Childrens Press, 1994. (0-51606-678-1)
Kratt, Chris. Creatures in Crisis. New York: Scholastic, 1997. (0-59006-605-6)
Lauber, Patricia. Alligators: A Success Story. New York: Holt, 1993. (0-8050-1909-X)
Ling, Mary. Amazing Wolves, Dogs and Foxes (Eyewitness Junior series). New York: Knopf, 1991. (0-67991-521-4)
Matthews, Downs. Wetlands. New York: Simon & Schuster, 1995. (0-671-86562-5)
Milkins, Colin S. Discovering Pond Life. New York: Bookwright, 1990. (0-531-18304-1)
Muench, David. Discover America: The Smithsonian Book of the National Parks. Washington, DC: Smithsonian, 1995. (0-89599-050-4)
Muir, John. Our National Parks. San Francisco: Sierra Club Books, 1991. (0-87156-626-5) Naden, Corinne and Rose Blue. John Muir: Saving the Wilderness. New York: Millbrook, 1990. (1-56294-110-0)
Parker, Steve. Pond and River. New York: Knopf, 1988. (0-394-99615-1)
Patent, Dorothy Hinshaw. Gray Wolf, Red Wolf. New York: Clarion, 1990. (0-89919-863-5) ________. Places of Refuge: Our National Wildlife Refuge System. New York: Clarion, 1992. (0-89919-846-5)
________. Return of the Wolf. New York: Clarion, 1997. (0-39584-519-X)
Patten, J.M. Oil Spills. Vero Beach, FL: Rourke, 1995. (1-55916-096-9)
Penny, Malcolm. The Food Chain. New York: Bookwright, 1988. (0-53118-167-7)
Petersen, David. Grand Canyon National Park. Chicago: Childrens Press, 1992. (0-51602-197-4)
Pick, Christopher. America's National Parks. New York: Crescent, 1993. (0-51602-197-4)
Pirie, Donald. National Park Vacations: the West. Boca Raton, FL: Cool Hand Com., 1994. (1-56790-012-7)
Pollack, Steve. Atlas of Endangered Animals. New York: Facts On File, 1993. (0-81602-856-7)
Rood, Ronald. Wetlands. New York: HarperCollins, 1994. (0-06-023010-X)
Rosen, Michael. All Eyes on the Pond. New York: Hyperion, 1994. (1-56282-467-7)
Sibbald, Jean. The Manatee. Minneapolis: Dillon, 1990. (0-87518-429-4)
Silver, Donald. Pond. New York: McGraw-Hill, 1997. (0-07057-932-6)
Simon, Seymour. Deserts. New York: Morrow, 1990. (0-68807-416-2)
Silverstein, Alvin. The Manatee. Brookfield, CT: Millbrook, 1995. (0-76130-163-1)
________. Saving Endangered Animals. Hillside, NJ: Enslow, 1993. (0-8949-402-7) Stidworthy, John. Ponds and Streams. Mahwah, NJ: Troll Associates, 1990. (0-8167-1963-2) Stille, Darlene. Water Pollution. Chicago: Childrens Press, 1990. (0-516-01190-1)
Stone, Lynn. Endangered Species. Chicago: Childrens Press, 1984. (0-51601-724-1)
Tesar, Jenny. Endangered Habitats. New York: Facts on File, 1992. (0-81602-493-6)
Wallace, Marianne. America's Deserts: Guide to Plants and Animals. Golden, CO: Fulcrum, 1996. (1-55591-268-0)
Wright, Alexandra. Will We Miss Them? New York: Charlesbridge, 1993. (0-88106-488-2) Young, Donald. The Sierra Club Book of Our National Parks. Boston: Little Brown, 1990. (0-316-97744-6)

Teacher Resources
Churchman, Deborah. "Night in the Sonoran Desert."Ranger Rick Magazine, February, 1997.
Naturescope: Endangered Species: Wild and Rare. Washington, D.C.: National Wildlife Federation, 1989. (0-94505-111-5)
Roest, Michele. Animals Tracks Activity Guide. Washington, D.C.: National Wildlife Federation, 1995. (0-945051-59-X)
For more information on the life of John Muir, his impact on conservation, pictures, quotes,
activities and lesson plans visit the Sierra Club's website and particularly its John Muir Exhibit at http://www.sierraclub.org/john_muir_exhibit.

For a list of national parks with links to pictures, maps and information on each one, visit http://www.yahoo.com/Recreation/Outdoors/Parks/United_States/National_Parks
National Wildlife Federation for Kids Website (http://www.nwf.org/kids/).
 

*Required or highly recommended for lessons
 

Long Term Project Checklist

Put a check in the box when you have completed that part of the long term project.

r PART 1
Find out the name of your representative in Congress or your U.S. Senator.
Address an envelope to one of them. Below are the addresses.
 
 

For representative in Congress:
The Honorable
U.S. House of Representatives
Washington, D.C. 20515

For U.S. Senator:
The Honorable
U.S. Senate
Washington, D.C. 20510

 

r PART 2
Choose an animal from the Endangered Animals list that you would like to know more about. Go to the library and find two books with information about that endangered animal.

r PART 3
On a separate piece of paper, answer the following questions about the endangered animal you have chosen:
1. What is the name of the animal?
2. Where in the world can this animal be found? Be able to locate this place on a world map.
3. What type of habitat does this animal need? (Examples: tropical rainforest, ocean, desert)
4. What does this animal eat? Is it an herbivore, carnivore or omnivore?
5. What are the causes of it being endangered? (Examples: over-hunting, habitat loss, pollution)
6. Are people helping to save this animal from extinction? How are they helping?
7. If you wish, draw a picture of the animal.

r PART 4
Write a letter to your representative in Congress or U.S. Senator. Tell him or her why you care about endangered animals and why it is important to protect them. Tell him or her about a particular endangered animal you are concerned about.
 
 

Third Grade - Science - Ecology

Endangered Animals

Here are a few animals on the long list of endangered animals of the world.
These animals are in immediate danger of becoming extinct.

Giant Panda
Humpback Whale
African Elephant
Jaguar
Whooping Crane
Sea Turtle
Black Rhino
Sea Otter
Orangutan
Black-footed Ferret
Brown Pelican
Chimpanzee
Mountain Gorilla
Bengal Tiger
Desert Tortoise
Blue Whale