Top: Kids and Teens: School Time: Science: The Earth: Cycles (46)
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• Kids and Teens: School Time: Science: Environment

Olympic Hands on the Land - Cycles - From the National Park Service, animated diagrams of the water, nitrogen, and carbon cycles. Includes explanations.

Life Materials and Nutrient Cycles - How life shares materials, why we need each other's "leftovers," water cycle, carbon cycle, nitrogen cycle, and sulfur cycle, including diagrams.

Water What Ifs - Water Quality and Nitrates and Phosphates - Shows the inter-relationship of these surface water parameters.