What do bicycles, doorknobs, and screwdrivers have in common? All of them use wheels and axles to...

Of the six simple machines, the wheel and axle is probably the most recognized. But how does it h...

Do you know what a lever is? How can a lever help you? Through simple experiments and clear expla...

What do hammers, wheelbarrows, and brooms have in common? All of them are levers! Levers are simp...

What is work? You may think work is doing chores or going to a job, but you do work every time yo...

What do a doorstop, a butter knife, and the front of a boat have in common? All of them are wedge...

We''ve all seen screws, but how do they work? Why is it easier to screw something into somethi...

What is an inclined plane? How do you use a wedge? Using easy-to-understand examples and fun-t...

What do staircases, dump truck beds, and ramps have in common? All of them are inclined planes! I...

How does a pulley work? What is it? Colorful diagrams and fun-to-do experiments help you explo...

What do jar tops and water-bottle lids have in common? Both of them are screws! Screws are simple...

Audisee(R) eBooks with Audio combine professional narration and text highlighting for an engaging...