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by Jessica McBrayer
Topics: Fifth Grade, Science
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Have you ever watched an old movie were the actor falls into a pit of quicksand? He struggles and struggles until someone finally throws a rope to get him out. But just what make quicksand it so sticky and dangerous? Why can’t he simply swim out of it?

Quicksand is a soupy mixture of sand and water where sand is floating in and on the water. It is both a solid and a liquid at the same time, making it a trap to moving animals and people. Quicksand occurs when water has flooded an area of sand and then is trapped in that area. Floods, underground springs, or an earthquake can create ideal environments for quicksand which usually occurs around river beds. In this activity, your child will make her own quicksand to get a feel of how it can be fluid and solid at the same time.

What You Need:

  • One box of cornstarch
  • Large mixing bowl
  • Pitcher of water
  • Spoon
  • Gallon size zipper lock bag
What You Do:
  1. Pour ¼ of the box of cornstarch into the bowl, add a half a cup of water and stir. It might be easier to mix with your bare hands.
  2. Continue adding cornstarch and water in small amounts until you have roughly the consistency of honey. You should mix the entire box and 1-2 cups of water. 
  3. Now start to move your hands through the “quicksand”. Move them fast and move them slow. What’s the difference?  Is it harder to move quickly? Sink your whole hand into the mix and try to pull up the hand. That’s the sensation of being trapped in quick sand.
  4. Drop a toy animal into the quick sand and then try to pull it out.

Is there any way out of quicksand? Did you find the best way to get across your quicksand?  Thrashing around in quicksand is instinctive but that is the worst thing to do. Instead you should try to level out and float on your back in order to paddle to firmer ground. Knowing how to survive in quick sand may not be the most practical lesson, but it could come in handy, and provides an interesting experiment in states of matter like liquid and solid.

CAUTION: When you are done with your experiment you must put your quicksand into the gallon sized zip lock bag and throw it away. DO NOT put it down a drain.