IOWA 4-9 SCIENCE PROJECT

TEACHERS GUIDE for: Food Webs Reta Lemon
ECOLOGY.462 Grades 4-6

CONCEPT OBJECTIVES:
Through this activity students will develop and understanding of the inter dependency of living things upon each other in a network called a food web, and create a food web.

PROCESS OBJECTIVES:
Students will develop observing, and classifying skills

TEACHER NOTES:
This is the second in a series of cycles, Ecology.461 Sun, Air, Water, and Soil (S.A.W.S.), Ecology.462 Food Webs, Ecology.463 Food Chains and Ecology.464 Habitats.
In preparation for doing the exploration activity the following materials must be put together.
1. 1 skein of yarn in a ball. (colorful and cheap)
2. 1 colored tagboard circle 6-8" in dim. for each member of the class, with a safety-pin attached.
3. On these circles should be written the words, SUN, AIR, WATER, AND SOIL and then "critters" and plants that are familiar to the students. Be sure to include at least two
of each of the following categories.
A. Producer=any green plants, clover, flowers, grass
B. Herbivore=plant eaters, rabbit, deer, grasshopper
C. Carnivore=meat eaters, birds, fish, turtles, coyotes, fox
D. Omnivore=plant or meat eaters, man, bear, raccoon, and some birds
E. First order consumer could be a rabbit because it eats clover. (Clover is a producer)
F. An owl would be a second order consumer because it eats the first order consumer, the rabbit. If a hawk ate the owl it would be a third order consumer.
G. Decomposer=those "critters" and plants which help break down dead animals or parts of animals and plants into soil, molds, earthworms, lichen, insects.

MATERIALS:
For each group
1 clip board or hard writing surface.
Several sheets of typing paper.
1 pencil

EXPLORATION:
Turn all of the circles with the word side down. Have the students select a circle, turn it over and pin it to their shirt front so everyone can read what is written. The student should know what is written on the circle.
Have the students form a circle large enough to contain every member of the class and small enough so they just stand shoulder to shoulder. Allow enough room so that the web maker with the yarn can walk outside the circle. (This works very nicely outside)
Direct each student to consider himself/herself whatever the word is. If the word they chose is a robin, they become the robin. Then, have them consider what their "needs" are and who "needs" or "wants" them.
Determine from the class as a whole one thing that every living organism needs. When they choose SUN start the end of the ball of yarn in that persons hand, continue to AIR, WATER, and SOIL. Each person holds the yarn loosely but firmly, then continue by asking "What do these four items produce?" the yarn will then go to a plant, or plants. Continue questioning and placing the yarn in a students hand until every student is connected with the yarn. The students will quickly notice the likeness to a giant web.
As the students determine what animal will eat what other plant or animal encourage them to share why they think so. From this questioning the terms of the food chain, producer, herbivore, carnivore, omnivore and decomposer will be discussed.
After the web as been completed direct the students to think about what would happen if one part of this web would be broken or destroyed. They can discuss this with their neighbor as the web is retracted. (Have the students continue to hold the yarn until it is backed out of their hand to eliminate a tangling problem if this activity is done outside.
During the same class period or the following class period take the students outside to an area where at least four habitats are visible from the one point. These habitats should include if at all possible a stream bank, edge of the forest, woodland and open meadow.
Divide the class into four groups with each group going to a different habitat. In the selected habitat list all of the living things that would inhabit this environment. Next list what is needed and used by the living things in the environment.
A recording paper would include the following:

WOODLAND ENVIRONMENT
1. Owl - - Tree - -Water- - Frog - -duck weed.
2. Tree - -Soil - -Air - -Earthworm- - rain.
3. Soil - -Water - Fish - -bugs - - mites.
4. Soil - -Earthworm- -plant- -air- -bird- -worm

CONCEPT DEVELOPMENT:
In a large group discussion review the four basic elements that all living things need, the first link in the food chain, Sun, Air, Water and Soil. Check with each group to see if they have these listed as important parts of their environment. Review what would happen if any one of these elements was missing.
Then under each environment list some of the major living organisms that the students perceived to inhabit this area.
Together discuss what one organism produces that another may need or consume. Introduce the terms consumer and producer.
Discuss also, what would happen if there was no water, or no birds, or no trees, or no fish, etc.
Continue discussing the interdependence of one species of life with another or several others; natures food web or web of life.

APPLICATION
Each group of students will construct a food web for the environment they visited.
The following materials will be needed for the groups to create their food webs.
1. 1 4'x8' sheet of cardboard (the side of a refrigerator carton.)
2. 1 small skein of yarn (different color for each group)
3. Background paper for pictures or drawings for living organisms.
4. Fine line markers, pencils, masking tape, scissors.

Each student within the group will contribute at least two living things in picture or drawing to be included in the group food web. Drawings or pictures may be cut and mounted on colored background paper or put directly on the cardboard.
Encourage students to label the pictures, with herbivore, carnivore, omnivore, decomposer, or producer if they know.
The students can decide to put the yarn down first in a web with 12-18 points then add the pictures in the correct places as organisms depend upon each other, or they may choose to put the pictures down first, then connect them with the yarn.
Remind the students that if the yarn connects a bee to a tree they must be able to justify their connection.
Label the board with the name of the environments and add Food Web or Web of Life.

EVALUATION:
Teacher observations during the exploration activity and the product created in the application activity are good ways of evaluating the student.