Food chains, food webs, trophic levels, ecosystems, and human impact on the environment are easy to teach with these informational reading passages and activities. Your students will learn to think critically about the different food chains and food webs found in various ecosystems, how each part of the food chain is related to and dependent on the others, as well as keystone species and how they balance the environment, through these nonfiction passages, hands-on tasks, and reflection activitie