National Institute of Open Schooling
Occurrence and Extraction of Metals
Steel is a man-made alloy or a mixture of metals. Lesson 18 in this series of 36 focuses on metals and their extraction from Earth. Individuals read about, discuss, and answer questions after learning how people find most metals, the...
San Francisco Public Utilities Commission
Pesky Plastics: The Problem with Plastic
What can happen to the environment if plastic continues to pollute it? Learners read about the implications of plastic on health, water, and nature in a two-page reading passage. After they finish reading, they work on six comprehension...