Build It!

Amy Mainzer works at NASA’s Jet Propulsion Laboratory. She is the science consultant on a space-themed STEM TV show on PBS KIDS called Ready Jet Go! She created this activity for TIME for Kids.

Our world is full of machines. Some are simple machines, like a seesaw, which is a lever. Others are combinations of simple machines, called complex machines. A roller-coaster is a complex machine. Combinations of simple machines can create almost anything—even spacecraft. For example, landers like those sent to Mars use robotic arms to gather rocks. Those arms are simple lever machines.

Your task is to design and build a machine out of everyday objects. It will move an object from one place to another. Rube Goldberg (see below) was a master of such designs. What will you create? Ask a parent or teacher to share your creation on social media. Use the hashtag #tfkstem.

The Challenge

Use materials you have on hand to create a machine that puts a marshmallow into a cup.

Required Equipment

• Large marshmallow (or other small round object, like a pom-pom or ping-pong ball)

• Cup

• Table (or floor)

Optional Equipment

These items are just suggestions. You can select a few from this list or substitute other items you have available.

• Dominos

• Books

• Toy Car

• Cardboard or stiff paper

• Tongue depressors or Popsicle sticks

• Paper clips or coat hangers

• Paper-towel or toilet-paper rolls

• Tape

• Rope or string

• Rubber bands

Procedure

1. Assemble the equipment you will need to build your machine.

2. Position the cup a few feet away from you.

3. Your goal is to create a machine that can move the marshmallow into the cup on its own. Imagine a few options. Draw a design of your machine first if you want to spend more time planning.

4. Think about how to connect the different parts of your machine. Then get to work building it.

5. Test it. Put the marshmallow into your machine and see if it goes into the cup. If not, figure out what prevented it from going in the cup, then adjust your machine accordingly.

6. Challenge yourself! After your machine is successful, use the same materials to build a different machine that will accomplish the same goal. Or see how many times in a row your machine will successfully move the marshmallow into the cup.

Rube Goldberg was a cartoonist. He is known for his comic-strip pictures of complex, imaginary machines. These inventions used springs, feathers, and other everyday objects to complete simple tasks, like opening a window or scratching an itch. Devices of this type became known as Rube Goldberg machines.