Curriculum resources can be expensive—but not this one. An online textbook offers informational text for a complete high school Biology course. Topics include energy flow, body system, genetics, and evolution.

Learn how energy is passed along through living things in a food chain and web.

This interactive ebook "Pond Web" demonstrates a pond food chain. Students can click on the ? to find answers to questions posed in the text. Students are asked to retell the story using pictures provided at the end of the book.

Read to understand how energy and inorganic nutrients flow through a food chain in an ecosystem.