Goal: Demonstrate the danger of playing around grain bins.
Ages: Appropriate for all ages with adult supervision.
Must be supervised.
Box of cornstarch
Pitcher of room-temperature water
Medium/large mixing bowl OR a large jar
A large marble OR small plastic toy
What To Do:
1. Gather one box of cornstarch, a pitcher of room-temperature water, a medium to large mixing bowl OR jar large enough to fit a child’s hand, a mixing spoon, and a large marble OR small plastic toy.
2. Select a volunteer to help mix ingredients. Add cornstarch into the bowl and then the water. Have pre-measured amounts ready for the children to use so the mixture becomes the correct consistency. Stir until the mixture’s texture is similar to honey.
3. Ask the volunteer to stick his or her hand into the mix, move it around, and describe how it feels. They should respond that it’s sticky and it’s difficult to move their hand.
4. Next, drop the small plastic toy into the mixture. They’ll see it sink quickly into the mix and disappear underneath the surface. Ask your volunteer to try and retrieve the toy. It will be a slight challenge to get it out since the mixture should be thick.
5. Compare the effects of the volunteer’s hand and the toy sinking into the bowl to the effects of quicksand. They were pulled in and it was difficult to get them out, just as it would be if one of them fell into a grain bin.
Bringing It All Together:
The surface tension of the cornstarch and water mixture is being used to simulate the effects of what would happen if someone or something fell into a grain bin. Coincidentally, the results are similar to that of quicksand. The corn kernels in the grain bin act a lot like quicksand in that there are so many small particles inside the bin that they lose their friction and seem to pull down whatever object falls inside.
Be sure to remind children that playing on or near a grain bin is very dangerous; and if they see one of their friends or another child playing around one, to go and get an adult to help right away.