An ecosystem is a collection of living things and the environment in which they live. Ecosystems are formed by the interaction of a community of organisms with their environment. Ecosystems may be large or small. This module allows students to investigate the dependence of organisms on one another and their environments. Lessons will provide students with hands-on experiences that strategically transition them into increased mastery of scientific content. In addition, this unit will help students identify how the parts of an ecosystem interact, explain reasons why changes in environmental conditions affect the survival of both individuals and entire species, describe the characteristics of Earth’s major terrestrial biomes/aquatic communities and draw conclusions about the relationships between organisms that are competitive or mutually beneficial to one another. The lessons presented in this unit are aimed at providing supplemental activities to the resources (textbook, science kits, etc.) that are currently available in your classroom to teach this topic. By the end of this unit students should be able to synthesize information from multiple sources, for the purpose of deriving a conclusion about the dependence of organisms on one another within an ecosystem.