This learning resource focuses on the nutrient flow within the Crystal Marsh ecosystem. Students will explore how nutrients cycle between the atmosphere, hydrosphere, geosphere, and biosphere. The resource provides a glossary of terms related to the spheres, and activities designed to help students categorize various components of the marsh, visualize nutrient pathways, and understand the interconnections between different spheres through collaborative discussions. It emphasizes the importance of maintaining steady-state nutrient flow and encourages critical thinking regarding the impact of changes in the ecosystem.