Food Chains: Nature's Restaurant

Jane Schaffran
Bert Raney Elem.
Granite Falls, MN
including an activity from USDA-Ag in the Classroom-www.agclassroom.org
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Summary

In this investigation of food chains, students begin by making observations & recording evidence of the variety of living things in local nature site/park within walking distance of the school. Students use reference materials to research predators & food of the animals they observed, then illustrate food chains & explain how energy is being transferred. Students play "Weaving the Web" to illustrate how individual food chains create a food web.

Used this activity? Share your experiences and modifications

Learning Goals

Learning Goals:
1. recognize that organisms need energy to stay alive & grow, & that energy originates from the sun
2. create food webs & describe the relationships among producers, consumers, & decomposers in an ecosystem in Minnesota
Higher-order thinking skills:
-Comprehension:explaining the transfer of energy
-Application:using acquired information to create food chains, drawing conclusions-looking for evidence of life, ie. scat, homes, eat marks, etc.
Other skills to be developed:
-Practice making observations & recording evidence for their observations in science journals,presentation of research in a diagram
Key concepts:
-All living things get energy from food
-Green plants use energy from the sun to create their own food,
-The sun is the source of all energy
Vocabulary:
-Food chain
-Food web
-Producer
-Consumer
-Decomposer
-Ecosystem

Context for Use

This 5th grade life science activity requires a minimum of 3 class sessions of about an hour each. I place it at the beginning of the year in order to walk to the park/nature site while there is still plenty of life to observe & the weather is mild. Prior to the site visit we would have introduced the students to working in small groups,the nature of the science journal & the importance of using evidence to back up claims. The 1st day is spent at the park/nature site making & recording observations in science journals. Depending on the class size & dynamics, you may want extra adults along. Our park is on the Minnesota River & safety is an issue. The 2nd day is spent in the classroom on the introduction of vocabulary & research with several reference materials on local animals, including access to computers & field guides. The 3rd day, students create food chains & present them to the class. Students need a variety of art supplies & access to books & magazines, such as "Birds & Bloom", "Field & Stream", "Ranger Rick", all of which contain nature pictures.

Description and Teaching Materials

In this series of 3 life science lessons, students will explore all manner of living things in a local park in order to gain understanding of the flow of energy in an ecosystem among producers, consumers, & decomposers. They will do further research in the classroom & create a food web to present to the class. Students will participate in the "Weaving the Web" game to culminate the lessons & reinforce that the flow of energy begins with the sun.

Materials:
(you may want extra adults to accompany each group)
-Nature site
-Science journals
-Wildlife reference materials
-Magazines containing wildlife pictures
-Art supplies
-Ball of yarn
-Tape
USDA-Ag In the Clasroom-www.agclassroom.org activity sheets 1-8


Day 1 Field Observations:

o At the park, have students in small groups. Tell students they will be making observations to notice what variety of living things are in the park & recording their observations in their science journals.
o Explain that several animals will leave the area & hide when a pack of students arrives. Ask the class, "What evidence might you observe with your senses that will tell you an animal has been there if you can't see it?" Have the students discuss in their groups & write their ideas in their journals under the heading "Animal Signs". Share ideas with the class & add any ideas they didn't have. Some signs might be: bones, scat, feather/ fur, tracks, nests, animal sounds, chew marks, etc.
o Direct students to include the living thing & evidence such as, "saw a frog by the pond", "heard a pheasant" , "saw deer tracks", "smelled a skunk". Give the students 15 minutes to explore the area you have designated. Remind students to leave living things where they find them.
o Gather the groups & share their findings. Students may add to their lists. Direct groups to make categories for the living things & share their ideas with the group. Ask is there are any living things that didn't get on the lists, if no one came up with plants as a living thing.
o In their reflection on the day have the groups write down ideas about how the living things get their energy to live & grow.


Day 2 Food Chain Research & Presentation:
o Review the observations from the field trip. Begin a discussion on how all the living things get the energy to live & grow. Share ideas from their journals. As students discuss what the animals eat & what is eaten introduce the vocabulary words "consumer, carnivore, herbivore, omnivore, predator, prey, decomposer & producer". Write the words on chart paper. Students should copy the new vocabulary in their journals. Be sure to ask "Where do the producers get their energy to make their own food?"
o Introduce students to the term "food chain" to describe a sequence of producers & consumers, always including the sun as the original source of energy. Have groups check their journals for living things that could create a food chain & share with the group. Have the students tell what is similar in each scenario. Encourage the use of new vocabulary.
o Have students use nature reference materials to research the food & predators of different animals in order to come up with a new food chain. Have students illustrate their food chain by drawing and/or finding pictures from magazines.
o Students will share their food chains with the group, explaining the flow of energy throughout, beginning with the sun.
o Have students write 1 thing they learned & 1 question they have in their reflection.

Day 3 Food Web game:

o Download "Weaving the Web" from USDA- Ag In the Classroom-www.agclassroom.org Adapted from Project LEAP: Learning about Ecology, Animals, and Plants, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY 14853
o Cut out the pictures of prairie plants & animals from activity sheets 1-8. (There are 24 pictures, so manipulate to fit your class size.)
o Have a group discussion on any questions from the previous day.
o After reviewing the food chains & the flow of energy, introduce the new term "food web" which consists of many food chains that are interconnected.
o Have students tape a picture on their chest. Have them stand in a circle & introduce themselves as the plant of animal they represent. The student with the sun should stand in the middle of the circle. Have them look around the circle & ask themselves, "Who could I give my energy to?" (Who might eat me?) and "Who could give me energy?" (Who could I eat?)
o Give the "sun" a ball of yarn & holding the end firmly, toss it to someone who could use that energy (a green plant). When the green plant catches the ball of yarn, he should hold the string & toss the ball to someone else who could use the energy, (a rabbit, for instance). The ball of yarn is tossed until it reaches a carnivore that has no natural predator. Break the yarn to indicate a food chain. (The question will probably come up about omnivores, which students can decide could end a food chain or be eaten by a carnivore.)
o Ask how all the other plants & animals in the circle will get their energy. Other food chains must be made. Return the yarn to the sun & start another chain. This time the sun might throw its energy to the grass, the grass to the field mouse, and the field mouse to the great horned owl. Again, break the yarn, & throw it back to the sun to start another chain. Continue until every student holds at least 1 strand of yarn.
o Ask:
Have we made food chains?
What do all of our food chains together look like?
What is the difference between a food chain & food web?
Who is holding the most pieces of yarn? Why?
Who else is part of many food chains?"
What would happen if all the green plants died?
o Ask:
How could we show what could happen if one kind of plant, such as all the clover died? (The student representing the clover could pull out his pieces of yarn & sit down.)
If all the clover is gone, who may have trouble getting enough food? (Identify all the animals that were in food chains that included clover. Whoever had yarn pulled out of their hands might have trouble getting enough food without clover.)
What happened to our food web? Why should we be concerned about each kind of plant & animal?

o Emphasize that each group is important & applaud each in turn.
Carnivores, please show your teeth.
Omnivores, please shake a leg.
Herbivores please wink an eye?
Will the only living things that can make food using the sun's energy please take a bow.
o Have student write a reflection on what they learned today & what they wonder about.

Teaching Notes and Tips

Last year I had students work on web sites to introduce food chains.
Food Chains
http://www.geography4kids.com/files/land_foodchain.html
Chain Reaction-a food chain
http://ecokids.earthday.ca/pub/eco_info/topics/frogs/chain_reaction/index.cfm#

This year I will be adding the field observation & use of science journals prior to creating food chains. I can have students use the web sites from my web page, on their own.

A reference book I think will be very helpful & specifically about Minnesota wildlife is Critters of Minnesota Pocket Guide by Adventure Publications, Inc. ISBN-1-885061-87-0.

I have used a game similar to "Weaving the Web" before. As an extension to the the activity students could name other ecosystems other than prairie, (forest, wetland, marine, etc.) & identify food chains from them.

Assessment

Students will be assessed on the acuracy of their food chain illustration & presentation to the class. They will be awarded points for having class assignments & reflections in their science journals.

Standards

5.IV.F. 1 & 2 Flow of Matter and Energy
5.I.A.2 Scientific World View-communication is essential to science

References and Resources