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.

Complex machines are really just collections of simpler machines working together. We can break them down into simple mechanisms, like wheels, levers, pulleys, ramps, screws, and wedges. Combinations of mechanisms can create almost anything—even spacecraft. For example, spacecraft use spinning wheels to turn and point. Landers like those used on Mars use robotic arms to gather rocks. Those arms are lever machines.

Your task is to design and build a simple machine out of everyday objects. It will move an object from one place to another, like the way a Mars rover collects objects from the planet’s surface and drops them into a container. 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.

• Books

• Toy Car

• Dominos

• Paper clips or coat hangers

• Cardboard or stiff paper

• Tongue depressors or Popsicle sticks

• Rope or string

• Paper-towel or toilet-paper rolls

• Tape

• 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 without any help from you. 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.