Easy science experiment for kids: Oobleck – the reluctant fluid
Here follow my instructions for the experiment to create a very strange fluid called oobleck. This is in my mind really fascinating. The first time my kids did this experiment, they couldn’t stop talking about it. 
Watch out, it can get messy!
Remember to start the experiment with a hypothesis, what do you think will happen?
Instructions for parents: Read this first.
Material included:
- 2 cups cornstarch
- Food coloring
- 1 (+2) cups water
Additional things you will need:
- Two bowls
- Trashbag to throw the oobleck in when you are done with the experiment
- A hammer
Description:
- Mix the cornstarch with the water and the food coloring in the first bowl. Take twice as much cornstarch as water.
- Pour 2 cups of ordinary water into the other bowl.
- Compare the two liquids.
- Stir the oobleck fast and slowly with a spoon.
- Hit the liquid with your hand or a with a hammer.
- Try to lift the oobleck up and form it as a ball in your hands.
Explanation:
Oobleck is a mixture of water and cornstarch where the cornstarch does not dissolve completely in the water. The cornstarch remains in microscopically small lumps.
Because there is so much cornstarch in the mixture, these lumps are so close that they nudge each other. If you put down a finger in the mix slowly, the lumps slide to the side and make room for your finger. The mixture behaves as if it was a liquid.
But if you put down your finger fast, the lumps don’t have the time to move away, since they are relatively heavy. Now the mixture behaves as if it was firm.
You can get oobleck to dance to music, though oobleck has a quite strange taste of music due to that it prefers music with a lot of bass. Try this by using a speaker which is covered in plastic. Then put the oobleck on the plastic and start the music.
NOTE: Keep in mind that cornstarch should not be poured into the drain – can you figure out why? Put it in a bag and throw in the garbage instead or dilute the mixture with plenty of water.
To see others do the experiment look at this video:
Click the link to get to my Kids Christmas Calendar.
Do you have any questions or comments about the experiment? Just leave a comment below!
Thanks!
Marika