Gooey Oobleck

King Derwin is bored with the weather! He demands his court magicians make something new fall from the sky and soon the kingdom is flooded with gooey green oobleck. Bust boredom in your home with less drastic consequences by reading Bartholomew and the Oobleck and concocting a little kitchen chemistry.

What you’ll need:

  • 1½ cups of cornstarch
  • 1+ cup of water
  • green food coloring
  • glass mixing bowl
  • mixing spoon
  • newspaper or other covering for a work surface


This oobleck isn’t the sticky type that Bartholomew encountered, but it can get messy. Cover a table or countertop with newspaper before starting.

Measure 1½ cups of cornstarch into a bowl.  Slowly add in water, stirring with your hand. The cornstarch will not dissolve but becomes suspended in the water. This makes the viscosity of oobleck very unusual—it changes depending on the pressure or forces you to apply to it.

Encourage your child to experiment with the oobleck. Suggest poking the oobleck. Does your child’s finger go through it? What happens when your child squeezes a handful of oobleck then stops squeezing? Or pours some from a spoon back into the bowl?

If green oobleck is desired, add enough food coloring to get a bright shade. Then you’ll have another chemistry mystery to solve—how to clean green hands!

When you’re finished experimenting with oobleck, don’t pour it down the drain as it could clog kitchen pipes. Dispose of it in the trash.