Simple Machines for Kids: Levers, Pulleys, Ramps and Wheels (Grade 3 to Grade 5 Science)

Hi, I'm Luna from DoodleBeez. Today we are learning about simple machines. A simple machine is a tool with few or no moving parts. It helps us push or pull things more easily.

Simple machines do not make work disappear. Instead, they change how hard you push or the direction you push. Often you use less force, but you have to move it over a longer distance.

A lever is a stiff bar that turns on a point called the fulcrum. A seesaw is a lever. Push down on one end and the other end lifts up. The longer your side, the easier it is.

An inclined plane is a ramp. Lifting a heavy box straight up is hard. Pushing it up a gentle ramp takes less force, but you travel farther. A wedge and a screw are ramps too.

A pulley is a wheel with a rope around it. Pulling down on the rope lifts a load up, so it changes the direction of your force. Flagpoles and window blinds use pulleys.

A wheel and axle is a big wheel joined to a rod in the middle. When one turns, the other turns too. A doorknob is a wheel and axle. Turning the big knob easily spins the small rod.

Now it's your turn. You need to get a heavy wheelbarrow of dirt up onto a high step. Which simple machine could help? Pause and try. A ramp, which is an inclined plane, would help!

Great job! Remember, levers, ramps, wedges, screws, pulleys and wheels and axles are the six simple machines. They change the size or direction of a force. Practice simple machines in the Science Lab at doodlebeez.com. See you next time!