Offered by The National Park Service Air Resources Division, this Web site includes a series of five 1-2 hour educational activities related to understanding acid rain and air quality for children grades six through eight. The very simply designed site includes lessons on: The pH scale; Understanding the difference between an acid and a base; Understanding what gases contribute to acid rain; How acid rain is measured and monitored in the US; and Understanding weather maps and the importance of storm tracking. Also included is a collection of figures to supplement the lesson plans.