Summary

Hands-on lesson that explains eutrophication, when too many nutrients cause algae to overgrow in ponds and lakes. Students learn the difference between oligotrophic and eutrophic water, identify common nutrient sources, and explore how algal blooms can lead to low oxygen dead zones. The activity uses simple bottle or jar ponds with different fertilizer levels to track changes in water color, smell, clarity, and optional oxygen over time, plus discussion on how to prevent nutrient pollution.