• 52 Videos, Slides, Films

• 52 Natural resources
• 40 Land use
• 40 Water-supply
• 13 Earth sciences
• 13 Geography
• 13 Landforms
• 13 Physical geography
• 12 Biotic communities
• 12 Ecological regions
• 11 Ecological zones
• 9 Geology
• 9 Technical education
• 8 Agricultural education
• 8 Physical geology
• 6 Agronomy
• 4 Agricultural implements
• 4 Agricultural machinery
• 4 Agriculture
• 4 Air
• 4 Biology
• 4 Climatic changes
• 4 Farm equipment
• 4 Global warming

• 52 Films Media Group
• 52 Infobase
• 10 Camille S. DeBose (Firm)
• 9 PBS (Firm)
• 6 Green Planet Films (Firm)
• 5 CINEFETE (Firm)
• 3 Australian Broadcasting Corporation (Firm)
• 3 Kwanza (Firm)
• 3 National Geographic Digital Media (Firm)
• 2 Video Education America (VEA) (Firm)
• 1 CNN (Firm)
• 1 Canadian Broadcasting Corp. (Firm)
• 1 Discovery Education (Firm)
• 1 EPF Media Group (Firm)
• 1 First Pond Entertainment (Firm)
• 1 Looking Glass International (Firm)
• 1 MacNeil/Lehrer Productions (Firm)
• 1 Magic Lantern Media Inc (Firm)
• 1 McIntyre Media Inc (Firm)
• 1 Prime Entertainment Group (Firm)
• 1 Smith Productions (Firm)

• 52 English

• 2 Asia
• 1 Africa, Sub-Saharan
• 1 South Asia

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