| Polar Animals (3 titles) |
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| Pond Animals (8 titles) |
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| Pop Biographies (6 titles) |
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| Presidents of the United States (45 titles) |
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| Privacy in the Digital Age (6 titles) |
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| Professional Sports Leagues (6 titles) |
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| Protecting Our Planet (6 titles) |
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| Protest Movements (6 titles) |
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| Pro Wrestling's Greatest (5 titles) |
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| Punctuation (6 titles) |
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| Race and American Law (6 titles) |
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| Race and Sports (6 titles) |
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| Race in America (6 titles) |
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| Rain Forest Animals (6 titles) |
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| Rain Forest Life (6 titles) |
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| Real Monsters (6 titles) |
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| Reptiles (6 titles) |
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| Reptiles (Spanish) (5 titles) |
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| Robot Innovations (6 titles) |
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| Rocks and Minerals (5 titles) |
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