• 16 Videos, Slides, Films

• 5 Astronomy
• 5 Exploration
• 5 Outer space
• 5 Physical sciences
• 5 Space flight
• 4 Collective behavior
• 4 Language arts
• 4 Social change
• 4 Social movements
• 4 Sociology
• 3 American literature
• 3 Literature
• 2 History
• 2 World history
• 1 African Americans
• 1 Appreciation
• 1 Biodiversity
• 1 Biology
• 1 British literature
• 1 Civilization
• 1 Civilization, Ancient
• 1 Effect of environment on
• 1 Endangered ecosystems
• 1 Endangered species
• 1 Environmental degradation

• 16 Infobase

• 1 Europe
• 1 United States

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