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Science Experiment for Kids With Corn Starch

Cornstarch experiments involve inexpensive, readily available materials, and they also provide a fun, interactive way for kids to learn about non-Newtonian fluid properties. When cornstarch is mixed with a limited amount of water -- about half a cup of water for every cup of cornstarch -- it forms a fluid known as "oobleck," which has the consistency of pancake batter and possesses both solid and liquid properties. Other examples of non-Newtonian fluid include quicksand, silly putty, blood and ketchup. The following experiments are best done outside or on top of sheets of newspaper.

The Splash Test
- The splash test requires a wide container of any depth -- such as a baking tray or a basin -- filled with cornstarch-water mixture. For comparison, a container of water can be placed alongside it. To show the difference between the fluids in the two setups, a volunteer holds his hand flat over the top of each container and then slaps it down as hard as he can. The kids can take turns trying to make the cornstarch setup splash. When the non-Newtonian fluid is subjected to stress, its molecules rearrange and lock in such a way that no splashes are produced.
Cornstarch Speaker Monsters
- This cornstarch experiment for kids needs a powerful speaker playing an amplified, constant low-frequency sound (about 15 to 50 hertz). The speaker cone must be directed upward, with a protective layer of cling film stretched over it. When the cornstarch mixture is poured on top while the speaker is off, it just sits there in a puddle. When the speaker is turned on, however, the puddle begins forming weird tendrils, which appear to move on their own. Small bits may get thrown out of the setup, but they can be picked up easily and placed back in.
Cornstarch Egg Protector
- This egg drop test requires a raw egg, a zip-lock baggie and a stepladder, in addition to the cornstarch-water suspension. The egg is placed in the plastic baggie, which is then filled about 4/5 of the way with the non-Newtonian fluid. The earliest test drops should be done at moderate heights, with the kids holding the baggie over their heads before dropping. If the egg survives, the drop height can be increased by one or two feet.
Walking on "Water"
- The setup for this experiment is a common sight in many science fairs. A large basin or a small kiddie pool is filled with the cornstarch mixture. The challenge for kids is to walk across the fluid without sinking. The teacher can demonstrate the trick needed to do this successfully -- going really fast. The kids can take turns running across the pool, jogging in place or even jumping up and down on top of the fluid.

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