http://www.old-pz.gse.harvard.edu/ucp/curriculum/density/index.htm

	Overview Background Project Team Papers Curriculum Modules Density Ecosystems Pressure Simple Circuits Related Links Helpful Sites		Causal Patterns in Density Phenomena Lessons to Infuse into Density Units to Enable Deeper Understanding A printed copy of this module can be purchased at the Project Zero e-bookstore.   Acknowledgments Introduction Overview Challenges in Understanding Air Density What Students Need to Know About Matter, Mass, and Volume Instructional Approach Endnotes for Introduction Section 1: Visualizing Density: Density is Non-obvious Lesson 1: How Can Objects of the Same Volume Differ in Mass? Lesson 2: What Are Some Models That Help Us Think About Density? Resources for Section 1 Endnotes for Section 1 Section 2: Defining Density as a Relationship Lesson 3: What Patterns Can Be Found Between Mass, Volume, and Density? Lesson 4: How Can We Calculate Density From The Relationship Between Mass and Volume? Lesson 5: Why Is Density Considered a Property of a Particular Kind of Matter? Lesson 6: Do Liquids Have Density? Lesson 7: Do Gases Have Density? Resources for Section 2 Section 3: The Causes of Differences in Density Lesson 8: How Does Atomic Mass Contribute to Density? Lesson 9: How Do Atomic and Molecular Bonds Contribute to Density? Lesson 10: How Does Mixed Density Contribute to Overall Density? Lesson 11: What Does It Mean for Density to Have Multiple Contributing Causes? Lesson 12: Can the Density of Solids, Liquids, and Gases Change? Resources for Section 3 Section 4: The Role of Density in Sinking or Floating: Relational Causality Lesson 13: Dropping an Object into a Liquid: How Does Density Affect Sinking or Floating? Lesson 14: Layering Liquids: How Does Density Affect Sinking or Floating? Lesson 15: What Happens in Sinking or Floating When the Relationship Between Densities Changes? Resources for Section 4 Endnotes for Section 4 ©2005, President and Fellows of Harvard College, Understandings of Consequence Project