How to Make Oobleck

Making Oobleck

Place 1 cup (8 oz) of cornstarch in a large bowl. You can spend a minute mixing it around with your hands to get comfortable with its texture. It can help to briefly whip it with a fork to get out any chunks so that it is easier to stir later.

Add 4-5 drops of food coloring to 1/2 cup of water if you want a color. Though you don't need to use food coloring to make Oobleck, many people like to use it to make the Oobleck a really fun color, and even more exciting to play with than white putty. If you'd like to add food coloring to the Oobleck, drop it and stir it into the water first, before you add it to the cornstarch. This helps it distribute evenly. Use as many drops as you want for a richer color.

Stir ⁄2 cup (120 mL) of water into the cornstarch. You should always stir in half as much water as cornstarch, keeping them in the ratio of 2 cups of cornstarch for every 1 cup of water. Use either your hands or a mixing spoon to really mix the water and cornstarch as much as possible.

Test the Oobleck by grabbing a handful and trying to form a ball. The hardest thing about this is getting the recipe just right. It will rarely be exactly two parts corn starch, one part water, right on the dot. Humidity, food coloring amount, and water temperature will all make subtle changes. It should feel a bit like it is melting in your hands. If you can't form a ball (too watery), add more cornstarch in one tablespoon at a time. Mix it and test each time. If it isn't runny like a liquid when picked up, it is too thick. Add more water one tablespoon at a time.

Using Your Oobleck

Play with the Oobleck. At first, just take it out with your hands and have fun kneading it, hitting it, rolling it up into a little ball, letting it drip from your hands into the bowl, and molding it into a variety of shapes. You can also: Mix and match with other colors to make designs. Strain and drop the oobleck through strainers, strawberry crates, etc. to watch how it flows differently than water.

Experiment with the Oobleck. Once you're more comfortable with the substance, you should see what happens when you squeeze the goo hard, or when you let it sit for a minute before picking it up again. Here are some other Oobleck experiments to try: Make a ball out of the Oobleck by rolling it around quickly in your palms. Then, stop applying pressure to the mixture and it will flow out of your hands. Fill a pie plate with a thick layer of Oobleck and slap the surface with your open hand. You'll be surprised by how all of the liquid stays on the plate because of the force you applied. Supersize the pie plate experiment by filling a large bucket or plastic bin with Oobleck and jumping up and down in it. Take the Oobleck in the freezer, and try it. Try it in the heat too. Is there a difference?

Clean up the Oobleck. You can use warm water to clean the Oobleck off your hands, clothes, and even off of your counter. You can rinse a bit of it out of your bowl, but make sure not to let too much of it get down the sink. If you let it dry out, it turns into a powder that is easily swept, vacuumed, or wiped up.

Store the Oobleck. Place the Oobleck into an airtight container or a zip-seal bag. Take it out again later and have fun playing with it. If you're done with the Oobleck for good, DO NOT throw it down the sink, or it may clog your drain. Throw it in the trash instead. You'll likely need to re-add water to your oobleck to play with it a second time.