This week On The River we explore who eats who and how energy and matter is passed between plants and animals in the food cycle. We'll cover the roles of producers, primary consumers, secondary consumers and decomposers.

Grades: 4-8

Standards: 

• 5 LS2.A: Interdependent Relationships in Ecosystems
• 5 LS2.B: Cycles of Matter and Energy Transfer in Ecosystems

Supplemental Work:

• Make a list of everything you eat in a day and use your list to make your own food web.
• Write a story from the perspective of one carbon or nitrogen molecule that is cycling through the food cycle..
• Play the food web game with your class - stand in a circle, have one student be the sun and assign each one of the remaining students to be a producer, consumer or decomposer. Using a long piece of string have the students connect all of the organisms in the food web using the string (i.e. sun -> cottonwood -> caterpillar -> frog -> mushroom). Once the food web is complete, remove one or more organisms which have been poisoned by pesticides, these students must drop the string. Any of the remaining students who feel the string slacken (i.e. are connect to the dead organisms) must also drop their string. This continues until the entire food web has collapsed demonstrating the far reaching consequences of our actions humans.