This graphic from Ecology and Evolution of Darwin's Finches by Peter Grant presents data from the Galapagos Islands, showing that a severe drought put selective pressure on the population of Darwin's finches and resulted in a change in...

An extensive look at the efforts to save the Tower of Pisa from falling over.

This article describes some of the world's most well-known cartels, the Columbian drug cartels.

Interact with this world map from McDougal Littell/TERC to highlight different climate zones and see a photograph of each one. Ten climate zones are represented, including tundra, desert, humid subtropical, and others.

This interactive activity from NOVA Online shows four different ways in which caves are formed: by rainwater, waves, lava, and bacteria.

A profile of the life and leadership of Fannie Lou Hamer, a civil rights activist best known for her stirring testimony at the 1964 Democratic National Convention.

In this interactive activity from the Web site developed for the PBS series "Building Big," investigate hypothetical structural emergencies and figure out how to repair them.

In this interactive activity from NOVA Online, learn about a type of exploding star a Type II supernova that is so large it has a mass 10 times greater than the mass of our Sun.

Travel deep into the human body to see exactly where your DNA resides. From the NOVA: Cracking the Code of Life Web site.

Examine these graphs from the NOVA/ FRONTLINE Web site to see dramatic increases in the temperature of Earth's surface and greenhouse gases in the atmosphere.

How does DNA perform those all-important functions of replication and protein synthesis? This interactive feature, from the Web site developed for the PBS series "A Science Odyssey," will help you explore and understand the secrets of DNA.

Dive in and explore what makes this beautiful world so fragile. In this Web feature, from the PBS series "Evolution," discover how coevolution has shaped the ecological relationships among reef creatures.

This essay from NOVA: "Life's Greatest Miracle" explores the debate over the use of embryonic stem cells in scientific research.

This illustrated feature from the American Experience Web site highlights the frequently forgotten inventors of several useful, innovative technologies.

Meet chemistry professor Dr. John Conkling in this interview from the NOVA Web site and learn why fireworks are his passion.

Which dictates our existence? Is it our genetic makeup or the environment we grow up in? Kevin Davies offers an update on this long-standing debate, from the NOVA: "Cracking the Code of Life" Web site.

Why do hot air balloons float? This resource from the NOVA Web site offers a series of interactive activities that illustrates the physics of hot air balloons.

Follow the growth of a carcinoma from initial mutation to widespread metastasis in this feature from the NOVA: "Cancer Warrior" Web site.

At the online companion Web site of "Evolution," the seven-episode series on PBS, piece together clues to how one of our early ancestors looked as you examine images from four significant fossil finds of Australopithecus afarensis.

Play in our streams and see how exhibitionism has an evolutionary payoff in this simulation of John Endler's famous experiment. Includes background information and discussion questions.

The Biotechnology Institute, in conjunction with a special titled, "Cracking the Code of Life" from NOVA/WGBH television, presents this issue dedicated to explorations of the human genome, one of the most exciting and provocative areas...

Explore how the events and cultural and political changes that occurred in 1968 came to represent the upheaval and dramatic changes in American life during the 1960s. In this interactive lesson from WGBH, students develop a written...

Consider how U.S. foreign policy changed in the aftermath of WWII, and analyze the philosophical, geopolitical, and economic factors that influenced these changes. In this interactive lesson from WGBH, students develop a written argument...

Trace the causes and debates that led to the Spanish-American War, including "yellow journalism" press coverage, President McKinley's declaration of war, and sentiments about imperialism. In this interactive lesson from WGBH, students...