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The Sleigh
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The Solar System
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The Solar System, Meteors, and Comets
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6.4 |
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The Soviet War in Afghanistan
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5.1 |
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The Space Race
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The Space Shuttle
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The Stars: Glowing Spheres in the Sky
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5.4 |
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The St. Lawrence: River Route to the Great Lakes
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6.2 |
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The Storm
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The Sun
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6.0 |
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The Sun: Our local star
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5.7 |
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The Tigris and Euphrates: Rivers of the Fertile Crescent
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6.9 |
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The True Cost of Fashion
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7.4 |
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The True Cost of Food
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7.5 |
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The True Cost of Technology
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6.5 |
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The True Cost of Toys
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6.6 |
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The Underground Railroad
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6.9 |
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The United States in World War I: America's Entry Ensures Victory
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6.1 |
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The Universe and Its Stars
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The Universe, Black Holes, and the Big Bang
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6.5 |
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The Urals
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6.6 |
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The Victorian Home
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5.8 |
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The Vietnam War
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5.4 |
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The Viking's Revenge
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4.8 |
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Canada
USA
