The subject of play and children's connection to nature is a topic addressed in the following books.:
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Last Child in the Woods: Saving Our Children from Nature-Deficit Disorder by Richard Louv.
Author Richard Louv argues for the benefits of nature in childhood: creativity, science, connection to the Earth. He calls attention to a study indicating that 8-year-olds could identity media characters much more easily than they could identify the names of trees or insects.
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These naturalist authors describe their childhood experiences and offer an argument for why they believe experiences with the natural world are so important for children.
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This book offers a variety of fun, nature-inspired activities geared for the preschool through second-grade set.
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A practical guide for bringing nature experiments home to your young child.
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"This guide to outdoor activities in the park, playground, schoolyard, or sidewalk encourage children to get outside and play. Activities include games with balloons and Frisbees, pet shows, running a lemonade stand, being a street artist, and much more."
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Nature Spy by Shelley Rotner and Ken Kreisler.
A photographic picture book that encourages exploring the outdoors.
Check out your local library for more books on the subject of outside play and exploring nature.