• 24 History
• 12 Study and teaching
• 11 Climatic changes
• 8 Civilization
• 7 World War, 1939-1945
• 4 Communication
• 4 Fossil fuels
• 3 Alexander, the Great, 356 B.C.-323 B.C
• 3 Creative ability
• 3 Creative thinking
• 3 Critical thinking
• 3 Explorers
• 3 Global warming
• 3 Heads of state
• 3 Scientists
• 2 Caesar, Julius
• 2 Civil rights movements
• 2 Cleopatra, Queen of Egypt, -30 B.C
• 2 Cold War
• 2 Dictators
• 2 Discoveries in geography
• 2 Generals
• 2 Group work in education
• 2 Physics
• 2 Revolutions

• 52 ClickView (Firm)
• 12 Participate Learning

• 89 English

• 8 United States
• 3 France
• 3 Soviet Union
• 2 Egypt
• 2 England
• 2 Great Britain
• 2 India
• 2 North America
• 1 Africa
• 1 America
• 1 Austria
• 1 China
• 1 Cuba
• 1 Earth (Planet)
• 1 Everest, Mount (China and Nepal)
• 1 Germany
• 1 Greece
• 1 Iraq
• 1 Islamic Empire
• 1 Italy
• 1 Japan
• 1 Korea
• 1 Macedonia
• 1 Moon
• 1 Netherlands

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