Science
Strand III
Use Scientific Knowledge from the Life Sciences in Real-World Contexts

 

Science/Strand III
Content Standard 5
All students will explain how parts of an ecosystem are related and how they interact; explain how energy is distributed to living things in an ecosystem; investigate and explain how communities of living things change over a period of time; describe how materials cycle through an ecosystem and get reused in the environment; and analyze how humans and the environment interact. (Ecosystems)

 

Science/Strand III/Content Standard 5
Elementary

 

Science/Strand III/Content Standard 5/Elementary
Benchmark 1
Identify familiar organisms as part of a food chain or food web and describe their feeding relationships within the web.

Benchmark Clarification

All living things depend on each other to survive. The parts of a food chain or food web have special names that describe the feeding relationships with the web.

Students will:

  • Identify and categorize producers – they make their own food (plants)
  • Identify and categorize consumers – they depend on producers or consumers for their food
  • Identify and categorize decomposers – they break down dead plants and animals and return nutrients to the soil
  • Identify and categorize predators – they hunt other animals and devour their prey
  • Identify and categorize prey – they are animals that are hunted for food
  • Define food chain
  • Define food web.

Key Concept / Real World Context / Instructional Example / Assessment Example / Resources

 

Science/Strand III/Content Standard 5/Elementary/Benchmark 1
Key Concept
Words describing parts of a food web:

  • producer
  • consumer
  • predator
  • prey
  • decomposer
  • habitat
  • community

 

Science/Strand III/Content Standard 5/Elementary/Benchmark 1
Real World Context
Food chains and food webs involving these common organisms:

  • rabbits
  • birds
  • snakes
  • grasshoppers
  • plants

 

Science/Strand III/Content Standard 5/Elementary/Benchmark 1
Instructional Example

Benchmark Question: How are parts of an ecosystem related and how do they interact?

Focus Question: How are organisms linked together in a food chain or food web and what is the flow of energy in the chain or web?

Have each student make (draw) separate pictures of each member of a three-member food chain beginning with a plant. (For example: corn, field mouse, red-tailed hawk.) Each student will name and explain the roles of the members of his or her food chain to the class. Once done, the food chains will be stapled to a bulletin board, as shown below. Then students will use yarn to connect the predators within their food chains to the prey in other food chains. The resulting food web will demonstrate the dependence of living things on one another for survival and the interdependence of food chains, which form a food web. Next, have students attach paper arrows (pointing away from the plant) to the pieces of yarn to show the direction of the flow of energy. Paper arrows closest to the plant should be larger than the arrows further away from the plant to show that the amount of usable energy decreases.

Simple food chain example (direction of arrow shows flow of energy; size of arrow shows amount of energy):

Simple food web example:

Constructing: (SCI.I.1.E.1), (SCI.I.1.E.2), (SCI.I.1.E.3), (SCI.I.1.E.5), (SCI.I.1.E.6).

Reflecting: (SCI.II.1.E.1), (SCI.II.1.E.2), (SCI.II.1.E.4).

 

Science/Strand III/Content Standard 5/Elementary/Benchmark 1
Assessment Example

Give each student a poster (teacher-created using words or pictures) with six organisms circled. At least one of each of the following is represented on the poster: producer, consumer, predator, and decomposer. Using his or her poster, each student will choose four out of the six organisms and use them to construct a food chain. Each student will explain the feeding relationship within the new chain.

Place students in groups of three. Each student will contribute the four organisms from his or her food chain for a total of twelve organisms. Each group will then create a food web showing the interrelationships of the food chains.

Next, each student will choose one organism from his or her group’s web to eliminate. Each student will write a list of predictions about what will happen to the food web if the chosen organism is eliminated. (For example, if a hawk is eliminated from the “corn, field mouse, red-tailed hawk” food chain, the mouse population will increase and the amount of grain will decrease, because more grain will be consumed by the mice, making less available for consumption by livestock and humans…) Students will share their predictions and the reasons for each prediction with the entire class.

(Give students rubric before activity.)

Scoring Rubric

Criteria

Apprentice

Basic

Meets

Exceeds

Identification of feeding relationships

Recognizes that there are feeding relationships between organisms, but does not identify them specifically.

Identifies one or more feeding relationships.

Identifies at least three common feeding relationships.

Identifies common feeding relationships and also provides evidence of lesser known relationships.

Accuracy of predictions

Writes one prediction/ consequence but is unclear on the sequence of events/the reason.

Writes one or two predictions/ consequences and accurate reasons.

Writes three predictions/ consequences and accurate reasons.

Writes four or more predictions/ consequences and provides accurate reasons.

 

Science/Strand III/Content Standard 5/Elementary/Benchmark 1
Resources

Webliography.
http://mtn.merit.edu/mcf/SCI.III.5.E.1.html

Animal Close-Up Series. Charlesbridge.
“Nature’s Way.” Sing the Science Standards
(Songbook/CD).

http://scienceexplosion.indiegroup.com/
Pass the Energy, Please!
Shawn McKinney Dawn Publishing, 2000.