Can you design a container that keeps an ice cube from melting for at least 30 minutes?

  • No safety considerations
  • Beginner
  • 30 minutes

Prepare Ingredients

2 to 4
ice cubes, all the same size

Gather Equipment

small containers with lids, about 16 ounces each, both made of the same material, such as plastic containers, cardboard boxes, or mason jars
  • Scissors
  • Aluminum foil
  • Cotton balls
  • Waxed paper
  • Scrap paper
  • Fabric scraps
  • Cardboard
  • String
  • Rubber bands
  • Newspaper
  • Paper towels
  • Bubble wrap
  • Tape
  • Glue

Gather information: For this challenge, 1 small container will be your base. You’ll decide what materials to put inside of the container to keep it cold in there—this is known as insulation (“in-suhl-AY-shun”). After you build your design, you’ll test it by putting an ice cube inside of the container for 30 minutes and seeing how much it melts compared to an ice cube without insulation.

Think about other things you’ve seen that keep food cold on the go, such as lunch boxes, coolers, and thermoses. (See “Food for Thought” at the bottom of this page for more information.) What materials are they made from? What other properties or characteristics do they have?


Brainstorm your design: What materials will you use for your insulation? You can use as many materials as you like, as long as they fit inside your container and leave room for 1 ice cube. Think about:

  • Do you want a material that is thick? Thin? Fluffy? Hard?
  • What are different ways you could use a material? For example, you can fold, cut, or crumple paper and you can pull apart cotton balls into different shapes.

Build your design: Place your insulation materials inside of 1 container—don’t forget to leave room for the ice cube. Will you add insulation to the lid of the container? What materials will you use?

ice cubes, both the same size

Test your design: Place 1 ice cube inside the container with your insulation. Place second ice cube in second container (without insulation). Cover containers with lids. Set containers aside in a warm, sunny location for 30 minutes.


Observe your results: After 30 minutes, remove ice cubes from both containers. Which ice cube is larger? The larger ice cube melted less—meaning it stayed cooler. Did your design keep the ice cube cooler than the container without insulation? What would you change about your design?