There is a lot of talk about how 3D printing could revolutionize the way that we make stuff. But what is 3D printing and how does 3D printing allow us to make almost anything from nothing? Professor Tim Minshall, Head of the Institute for Manufacturing at the University of Cambridge, explains it in this video, which is targeted at school-age students.

They can flow like a liquid and bounce back like a solid. Masses of fire ants show a duality that intrigues physicists.

You've made it to the final round of a game show, and get to pick between 3 doors, one of which has a car behind it! You make your choice, and then the host decides to show you one of the wrong answers. He then offers you the opportunity to change your choice. Should you do it? Find out just how wrong human intuition can be in this classic Monty Hall Problem.

Why do some of the national parks in the United States resemble the European Alps? Geologist Dr. Robert Darga answers this question.

Why are some rock formations and animals found on more than one continent? The explanation dates back to the Ice Age.

In Yellowstone Park, visitors can see many indigenous animals in their natural habitat and wonder at the park's natural hot springs.

Geysers represent a very popular tourist attraction in Yellowstone Park. How do they work and where do they come from? And what is sandstone? The video answers these questions.

In this segment, we learn about the role weather plays in the creation of rock formations in the national parks of the United States.

We learn more about how water interacts with the minerals in the rocks, and visit Monument Valley, a popular spot for filming westerns and commercials.

The Colorado Plateau and the Grand Canyon are just a few of the amazing geographical features of the Southwestern United States.