Assess students' ability to design a closed terrarium mini-ecosystem that can sustain plants and small animals (e.g., snails or worms) for four weeks by specifying appropriate plant and animal species, providing a complete materials list and setup plan, stating a clear testable hypothesis, identifying controlled and measured variables, and producing a week-by-week data-collection and testing plan (observations, measurements, safety considerations, and criteria for success); evaluation emphasizes scientific reasoning, feasibility for grades 3–5, and troubleshooting strategies.