Describes the isolated Nevada air base known as Area 51, covering its use for testing top-secret aircraft, and discusses speculation about a connection to unidentified flying objects.

Describes different types of submarine vehicles and their development, discussing their various uses for military purposes, undersea exploration, and ocean research.

In the 1990s, scientists lived inside Biosphere 2 (Biosphere 1 is the Earth itself) for two years, trying to figure out if colonizing Mars would ever be possible. Now scientists don't live there but instead conduct all sorts of studies and experiments aimed to help us better understand our environment and especially understand what sort of things are happening to it due to climate change and other man-made problems. It's a unique take on the Scientists...

Photographs and text recount Caitlin O'Connell's experiences observing African elephants in their natural habitat, describing the discoveries she made about elephant communication.

Engaging images accompany information about Area 51. The combination of high-interest subject matter and light text is intended for students in grades 3 through 7--