The Fishing Ecosystem (I770) is a hands-on material designed to help elementary-age children explore the interdependencies within an aquatic ecosystem, including predator-prey relationships, food chains, and environmental balance. It supports the lower elementary child's emerging capacity for abstraction and cause-and-effect reasoning within the Going Out and biology threads of the cultural curriculum. This material lends itself well to small group work and can anchor a broader study of ecology or serve as a concrete entry point before children move into research-based exploration.