See an aerial view of how communities around the globe have changed over time.

Instructional module focusing on Charles Darwin's explanation of natural selection as the mechanism for evolution. Discusses how this force of natural selection promotes changes in species over time. Site also includes an interactive...

The student will compare and contrast the different modes of transportation during the early 20th century and present-day America using historical photographs. Included are links to photos, a printable worksheet, and extension and...

Through amendments and legal rulings, the Constitution has transformed in some critical ways. The U.S. Constitution, written in 1787 and ratified by nine of the original 13 states a year later, is the world's longest-surviving written...

While certainly not inclusive, this article not only identifies thirteen top tappers, but also offers videos of each of them. While the first few in the list would be considered early tappers, like Bill "Bojangles" Robinson, this...

[Free Registration/Login Required] This New York Times interactive lets you type in name of your hometown (or any town) and the year of your birth. It will then show you the number of increased days the temperature there has been over...

Online lesson plan to teach the concept of historical understanding by studying how a community changes over time. In this case, we look at the South Side of Chicago and ask, What happened here? Why did this place change? How am I...

An explanation of how the Earth's atmosphere has changed over time. Evidence that helped scientists understand these changes is presented.

Examine the power of Congress to make war by studying primary source documents from various wars throughout U.S. history. Students will analyze how the balance of authority between the legislative branch and executive branch has changed...

Given a function that models an exponential situation, find the time interval over which the quantity changes by a given factor.

What did Denver look like millions of years ago? Find out the answer to this and see how it has changed over time. There is also a list of parks to visit in Colorado.

This learning module looks at how normal behavior is defined and perceived by society. The definitions of normal behavior shifts as societal norms change over time. The Diagnostic and Statistical Manual of Mental Disorders (DSM) is a...

From twentieth-century posters, monuments, and letters to nineteenth-century maps, biographies, and paintings, this set allows students to gain a greater understanding of how perceptions of manifest destiny have changed over time.

Article discusses the history of English dictionaries over a five-hundred-year period. Includes selections from Samuel Johnson's dictionary of 1755 and the Oxford English Dictionary. With useful comments about the origins of words,...

NASA's Scientific Visualization Studio uses data from several sources to track seasonal changes in Arctic sea ice and land cover over time. Scientists study sea ice because it influences global climate. Watch the following visualization...

Gain knowledge of how exploration, mapping, and voyages of the Renaissance period shaped and changed our understanding of the modern world.

A learning module on American immigration policy that includes several supporting questions accompanied by formative tasks and source materials, followed by a summative performance task. Topics covered include the debate over immigration...

Read about the history of asphalt beginning in the city of Babylon around 615 BCE. Learn how Europeans and Americans began to use it on roads, how businesses competed for a market share and even patented roads, changes to asphalt...

Students investigate the impact John F. Kennedy's assassination has had on American politics since that event. After his death, Lyndon B. Johnson pushed through the Civil Rights Act of 1964 and the Voting Rights Act, both of which had...

By the end of this section, you will be able to calculate power by calculating changes in energy over time and to examine power consumption and calculations of the cost of energy consumed.

Students investigate changes in the surface temperatures of the Gulf Stream over the course of the seasons using data collected by NASA's satellites. The data is inputted into a spreadsheet and graphed.

Evolution is the change of inherited characteristics within a population over time through natural selection, which may result in the formation of a new species.