The first site related to pH is from the Horiba corporate Web site entitled the Story of pH (1). Visitors can learn what pH is and how it's measured, explore various facts about pH, and read several anecdotes such as "Is the Rain in Our Cities Acidic." The site contains simple text, attractive graphics, and a well-designed layout making it fun and easy for anyone to explore. The second site from the Miami Museum of Science is called the pH Factor (2) kids activity page. This interactive and extensive site contains lessons on testing items for pH, tasting acids and bases, an interactive meter to find the pH of common household items, and much more. Next, is the pH and Water Quality (3) page, which is part of the State of Kentucky Division of Water Web site. The site provides a table of the effects of pH on fish and aquatic life and gives a short description of the most significant environmental impacts of pH. Trout for example, can tolerate a pH range between 4.1 and 9.5 while Mosquito larvae can survive within the 3.3 and 4.7 range. The fourth site from Gardengate Magazine.com is entitled More Soil Stuff: Soil pH (4). Described is the pH range of most soil types, requirements of certain plants, how to test soil for pH, and how to adjust it using sulfur and limestone. Seaworld.org maintains the Understanding the pH Cycle within the Aquarium (5) lesson plan site. The stated objective of the activity is to have students define pH, explain how it affects a tank's water quality, and test the pH level in a classroom aquarium. Although an aquarium is obviously needed, the activity offers a unique and fun way for kids to learn about this basic chemistry concept. About.com offers the next site, which is an interactive pH calculator called pH (6). Users simply enter a pH to get the concentration of Hydrogen ions or, conversely, the Hydrogen ion concentration to get the pH. Another tool to learn about pH and Hydrogen ions is called Acids and Alkalis--the pH Scale (7). Provided by Purchon.com, the interactive pH scale illustrates how the ion concentration changes with pH, common acids associated with each, and whether it is a weak or strong acid or alkali. The last site maintained by the National Park Service is called Acid Rain Lesson Plan: Activity 1 The pH Scale (8). Kids will be able to describe the pH scale and its components, explain why a pH measurement must be accurate, and explain why small changes in pH are important. Everything needed to complete the activity is provided, including a materials list, complete instructions, thinking questions, as well as links for further information.