A printed copy of this module can be purchased at the Project Zero e-bookstore.
	Acknowledgments
	Introduction Overview Challenges in Understanding Ecosystems Instructional Approach Suggestions from Teachers Endnotes for Introduction
	Section 1: Understanding the Connectedness of Ecosystems Using Domino Causality Understanding Goals Background Information Lesson Plan: Exploring the Web of Life Reinforcement Activities Resources for Section 1 Endnotes for Section 1
	Section 2: Learning about Decay Using Cyclic Causality Understanding Goals Background Information Lesson Plan: Learning About Decay Reinforcement Activities Resources for Section 2 Endnotes for Section 2
	Section 3: Thinking About Obvious and Non-Obvious Causes of Decomposition Understanding Goals Background Information Lesson Plan: Comparing Worm and Worm-free Compost Tanks Reinforcement Activities Resources for Section 3 Endnotes for Section 3
	Section 4: Decay Takes Time: Detecting Causal Relationships Despite Temporal Delays Understanding Goals Background Information Lesson Plan: Using Time-Lapse Video to Reveal The Cycle of Decay Reinforcement Activities Section 4 Resources Section 4 Endnotes
	Section 5: Two-Way Causality and Ecosystem Interdependencies Understanding Goals Background Information Lesson Plan: Exploring Instances of Two-Way Causality in Ecosystems Reinforcement Activities Resources for Section 5 Endnotes for Section 5
	Section 6: Understanding Balance and Flux in Ecosystems Understanding Goals Background Information Lesson Plan: Balance and Flux Reveal How Organisms Are Connected in Ecosystems Reinforcement Activities Resources for Section 6 Endnotes for Section 6