Science ZipKit: How to Stay Warm


Test a "Polar Bear Blanket"

What you need What to do
  • Bag of ice water
  • 2 Ziplock bags
  • 12-15 cotton balls
  1. To make a Polar Bear Blanket, zip cotton balls in one bag. Zip the empty bag shut.
  2. Work with a partner. Hold out your hands, palms up. Ask your partner to put the blanket on your palms. Then put the ice bag on top. Does your hand feel cold?
  3. Remove the bags. Put the empty bag on your palms. Put the ice bag on top of it. Does your hand feel cold?


This week's activity investigates how we use materials as insulation to keep warm. The word insulation will be new to your child, but the idea will be familiar. We all know that we put on more clothes in the winter to help keep our bodies warm, and when summer comes, we can wear shorts and T-shirts and not be cold. Try this experiment to demonstrate this idea for your child.

STEP #1-PLAN: Tell your child that you are going to use the materials in the bag to do an experiment about keeping things warm. You are going to put ice cubes in one Ziplock bag and then use the other stuff to try to keep your hand warm while you hold the ice. Plan what you would like to do.

STEP #2-PREDICT: After you have figured out a way to use the materials to keep your hand warm, predict which way you will be able to hold onto the ice bag longer-just putting the ice in your hand or using your insulation?

STEP #3-OBSERVE: Which method worked better? Did your hand get cold at all when you used the bag of cotton balls to insulate it? What else do you have around the house to use in the bag for insulation? Try things like wadded up newspaper or a pair of socks. Do they work? Which method works best?

STEP #4-REPORT: Draw a picture or write in words which way you thought worked best. Or, draw a picture of your face when you held the ice without the insulation. How did you feel?

Extra Questions:
  1. How do animals that live outside stay warm in the winter?
  2. What happens to ice if you leave it out in a glass? Would wrapping in up in something make it melt faster or slower? Try it!



Last updated: November 22, 1997 by Charles S. Yang