Wham! Wham! Wham! All it takes to nail two pieces of wood together is a few strong hits with a hammer. But fastening two pieces of wood together with a screw is a lot harder. The screw has to be...
A shape that works
Be careful---that knife is sharp! Don't stick yourself with that needle! Working with sharp things means taking special care. But some things have to be sharp to work well. A dull knife or a needle...
Slides and steps
Is a slanted board a machine? It is if you use it to do some work. It's a kind of simple machine called an inclined plane. Inclined means \"slanted," and a plane is a flat surface. So an inclined...
Make an alligator long-arm
Levers make it easier to lift big and heavy things. They can also help you pick up things you can't quite reach. This alligator long-arm uses pairs of levers to make other levers move. Use the ruler...
A lever is clever
How many times can you lift your best friend higher than your head? How many times can your best friend lift you? It doesn't sound easy, but it is---and it's fun, too. When you and your friend are...
Easy as one-two-three
Whirr! The faster you turn the handle, the faster the eggbeater goes. Pretty soon the eggs are a froth of golden-yellow bubbles! The eggbeater makes the work easy---much easier and faster than if you...
Machines Make It Easy
Machines Make It Easy Machines Make It Easy
Putting electricity to work
> It may look a bit like a dragon, and it may > > roar like one---but it's really only a vacuum cleaner. And the thing > that makes it gobble > > up dirt from a rug is an electric fan! > > When...
Putting energy to work
You can water your garden by holding the hose and spraying the water where you want it to go. But if you do this, you have to stand there until the garden is watered. There is another way---a better...
Windwagon Smith
The story of Windwagon Smith is actually a \"tall tale" that was made up by American frontier people more than one hundred years ago. Whoever made up the story was aware that wind is a powerful...
