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    Understanding Metaphors
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    Understanding Native American Myths
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    6.5   | 
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    Understanding Norse Myths
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    6.5   | 
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    Understanding Our Sun
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    6.9   | 
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    Understanding Personification
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    Understanding Roman Myths
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    6.5   | 
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    Understanding Sayings
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    Understanding Similes
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    Understanding the American Revolution (8 titles)
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    Understanding the Articles of Confederation
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    Understanding the Bill of Rights
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    Understanding the Civil War (8 titles)
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    Understanding the Declaration of Independence
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    Understanding the US Constitution
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    United States: The Culture
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    7.5   | 
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    United States: The Land
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    7.8   | 
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    United States: The People
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    7.4   | 
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    Universal Health Care
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    Unlocking the Secrets of the Solar System
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    6.6   | 
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    Un mal día para Mia (Mia's Bad Day)
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    Unsolved! (12 titles)
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    Unsolved!
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    5.7   | 
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    UN Sustainable Development Goals (4 titles)
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    Unusual Animal Journeys
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    5.9   | 
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