Cómo funcionan las ruedas y los ejes

Readers won't have to disassemble their favorite toys to discover what makes them work. This book explores electric, magnetic, and motion-powered toys from design to function. It introduces readers to the six simple machines and explains how they use force and motion to do work. Not every toy is a technological marvel. Readers learn about time-honored favorites including the rocking horse, Slinky, and rattles.

Looks at the different colors used to draw and paint artwork. Includes instructions for creating a fish using many different colors.

The United States grew rapidly from the time of the Louisiana Purchase to the building of the Transcontinental Railroad. All of this expansion came at the expense of Native American populations that had either lived in the region for centuries or been forced there from ancestral homes in the East. Tribes memorably fought on their own and together in an doomed effort to retain the land and a lifestyle that had long sustained their families. This book outlines some of the major conflicts of the Westward Expansion, and of the treaties and were signed, and often broken, by representatives of the...

Filled with tricks and treats, fun and food, Halloween is a day that children look forward to. At one time two separate festivals, the traditions of each gradually blended into the holiday we now celebrate on October 31.