An extensive investigation of the Earth's climate changes awaits your environmental science classes. This top-notch presentation begins by looking at the history of Earth's climate and then predicts the impact on each major terrestrial...

Upper elementary meteorologists take a glance at what a hurricane is and how it is formed. Because this does not get into the differences in air pressure that drive the associated winds, it may not be useful for older learners. The...

Aristotle explained the idea of spontaneous generation, a concept which lasted almost 2,000 years before scientists proved it wrong. Scholars learn about the history of our understanding of the origins of life. They read examples of...

When crocodiles close their mouths, you still see their teeth, but when alligators close their mouths, their teeth are hidden. Learn more about these reptiles and their many evolutionary cousins in a fact-filled presentation. It...