Simple Machines
Background Information & Activities

Discuss with your children how they use machines to make work easier. You may want to identify machines your children use often such as a bus, a stapler, or a bike. A simple machine is a tool that uses force to make work easier. While machines can have many moving parts, a simple machine has none or very few moving parts. Simple machines need a single force to operate. A ramp, lever, pulley, and a wheel and axle are examples of simple machines.

Explain to your children that a force is a push or pull that can change the way something moves. For example, when you throw a ball you use a force to make it move. When you catch a ball, you use a force to stop its motion. Any push or pull is a force. Review with your children that heavier objects require more force to move. For example, a bowling ball is harder to throw than a table tennis ball. Some objects are so heavy that people need machines to use them. A simple machine can use force in different ways to make work easier. It can change the way a force is used to make it more effective.

A ramp is a simple machine with a slanted surface. It helps people and things move between higher and lower places. Discuss different ramps your children have seen or used, such as moving ramps, disabled ramps, or slides on the playground. Explain that it takes a lot of force to lift up and move something heavy, but it’s much easier to push it up a ramp. It is much harder to move things up steeper ramps, or ramps that go up higher, similar to the way it is harder to walk up a bigger or steeper hill.

A lever is a simple machine that consists of a bar that rests on a fulcrum, or a point that does not move. A seesaw is the classic example of a lever. When force is applied to one side and is pushed down, the other side lifts up. A lever can help lift up heavy loads. Bottle openers, scissors, and staplers are common items that use levers.

A wheel and axle work together to make a simple machine. Explain that a wheel turns around a rod, called an axle. A wheel and axle can help move things faster or more easily and help things turn. Carts, skateboards, roller skates, bikes, and cars all use wheels and axles. Explain that heavy things can be difficult to push across a surface and can require a lot of force. But, if you add wheels to the bottom, it becomes much easier. Have your children give examples of how wheels and axles make work easier.

A pulley is a simple machine that has a rope or cable that goes over a wheel. A pulley helps people lift things up and change the direction of their force. You pull down on a rope to make the load go up. You can connect pulleys together in order to use less force to lift up a load. Clotheslines, flagpoles, and blinds use pulleys.

Help your children understand that machines can combine many different simple machines to make work easier. For example, a crane uses levers, wheels and axles, and many pulleys to lift up heavy objects. Learning about simple machines and forces is a great way to teach the fundamental of physics and help children understand the world around them.

Simple Machines Teacher Activities – Click Here!

Simple Machines Family Activities – Click Here!

Simple Machines Teacher Activities

Ramping Up

Have small groups or pairs create ramps using a book and building blocks. Then give each group a mini-car, cylinder, or other object with wheels or a curved surface. Have your students roll different objects down the ramp and measure the distance they went. Then have them change the steepness of the ramp by adding or taking away blocks. Students can do the activity again and then see how the distance traveled changed. Have groups share their results with the class.

Pulley Message System

Have small groups make their own pulley. Take two small spools of thread and put a pencil through the center. Then tie the ends of the string together to create a loop. Have two students hold the pencils and spools and spin them slowly to create a pulley system. Then have another student write messages and attach it to the thread using a paper clip. Pass the message from one person to the other.

Simple Machines Family Activities

Simple Machine Walk

Together with your child, take a walk around your neighborhood. Have your child carry a notebook or a camera. Have him or her identify different simple machines or observe machines or tools that use different simple machines. Have your child take pictures of it or draw a picture of it to make a catalog. As a math connection, have your child create a tally chart to keep track of the number of different simple machines he or she sees on the walk. Which simple machine is most commonly used?

Give a Lift

Tape a pencil to a table. Then place a ruler on top of the pencil to create a lever. Place an object on one end of the ruler and press down on the other end to lift the object up. Try using objects of different weights. What happens? Is it easier or harder to lift heavier objects? Then have your child move the ruler so that the fulcrum is closer or farther away from the load. When does it become easier or harder to lift the load?