Sally M. Walker

The members of the Vowel family have a hard time talking until their children, Alan, Ellen, Iris, Otto, and Ursula, are born, and when one of them gets lost one day, it takes their Aunt Cyndy to fix the problem.

Introcuces reefs, including how they are made, their importance to the environment, and why they are endangered.

Describes the hydrologic cycle and its importance to life on Earth.

What do jar tops and water-bottle lids have in common? Both of them are screws! Screws are simple machines. They help us to do jobs more easily. But don't take our word for it. Put screws to the test with the fun experiments you'll find in this book. This series sheds light on a key science question; How Do Simple Machines Work? Hands-on experiments, interesting photos, and useful diagrams will help you find the answer!

What do staircases, dump truck beds, and ramps have in common? All of them are inclined planes! Inclined planes are simple machines. They help us to do jobs more easily. But don't take our word for it. Put inclined planes to the test with the fun experiments you'll find in this book. This series sheds light on a key science question; How Do Simple Machines Work? Hands-on experiments, interesting photos, and useful diagrams will help you find the answer!...

What do a doorstop, a butter knife, and the front of a boat have in common? All of them are wedges! Wedges are simple machines. They help us to do jobs more easily. But don't take our word for it. Put wedges to the test with the fun experiments you'll find in this book. This series sheds light on a key science question; How Do Simple Machines Work? Hands-on experiments, interesting photos, and useful diagrams will help you find the answer!

On July 28, 1996, two young men stumbled upon human bones in the shallow water along the shore of the Columbia River near Kennewick, Washington. Was this an unsolved murder? The remnants of some settler's or Native American's unmarked grave? What was the story behind this skeleton? Within weeks, scientific testing yielded astonishing news: the bones were more than 9,000 years old! The skeleton instantly escalated from interesting to extraordinary....