How to Make Goo

Viscoelastic or Non-Newtonian Slime Recipe

This non-toxic goo hardens like a solid when you squeeze it but flows like a liquid when you pour it.
This non-toxic goo hardens like a solid when you squeeze it but flows like a liquid when you pour it. PamelaJoeMcFarlane / Getty Images
Updated February 13, 2017

Make squishy non-toxic goo that hardens in your hands when you squeeze it, but flows like a liquid when you pour it.

Difficulty: Easy

Time Required: minutes

Goo Materials

All you need for this project is corn starch and water. You can add food coloring, if desired. Feel free to experiment with the amount of water to see how it affects the properties of the goo.

  • 16-oz box cornstarch
  • water
  • food coloring
  • bowl

    Let's Make Goo!

    1. Empty the box of cornstarch into a bowl.
    2. Add 1-1/2 cups of water.
    3. Add about 15 drops of food coloring. It's fine without color, too.
    4. Mix the goo with your hands.
    5. You can store goo in a sealed container when you're done using it. If it dries out, simply add more water.

    Goo Characteristics

    Goo is a viscoelastic or non-Newtonian fluid, which means its viscosity (how readily it flows) depends on external conditions, such as pressure, shear, or tensile stress. If you pick up goo, it will run through your fingers. If you squeeze it or punch it, it seems to solidify. The force pushes the water around the corn starch particles, allowing them to mesh together. Afterward, the water flows back to fill in the gaps.

    Experiment With Other Liquids

    Water isn't the only liquid you can use to make goo. Try using vegetable oil or a mixture of oil and water instead. This forms a goo with interesting electrical properties.

    Watch how this type of goo reacts when you place an electrically charged object near it (like a balloon you rubbed on your hair).