Unit 1: Understanding Sustainability Unit 2: Building Community Unit 3: Waste Management and Recycling Unit 4: Green Building Unit 5: Energy Unit 6: Air Quality Unit 7: Water Quality Unit 8: Soil Quality Unit 9: Parks and Open Spaces Unit 10: Transportation Unit 11: Biodiversity Unit 12: Urban Agriculture and Community Gardens Unit 13: Urban Forestry Unit 14: Urban Planning Unit 15: Population Growth and Integrated Resource Management Unit 16: Environmental Justice Unit 17: Public Policy and Community Action Unit 18: Sustainable Commerce Unit 19: Green-collar careers.