This U.S. Census Bureau Web site has two population clocks with notes available. One clock shows the population increase for the United States. The other shows the world population increase.

[Free Registration/Login Required] An informational text about the increasing world population. A question sheet is available to help students build skills in reading comprehension.

With increasing pressure on the world's natural environment and resources it is essential that we develop farming systems that have a low impact on the environment, and are also highly productive in meeting the needs of a growing global...

In this lesson young scholars learn about the urban heat island effect by investigating which areas of their schoolyard have higher temperatures. Then they analyze data about how the number of heat waves in an urban area has increased...