Teaching with Cornstarch

Needed:

• 1 cup cornstarch
• ½ cup water (adjust for texture)
• Large clear bowl or tray
• Optional: food coloring
• Paper towels for cleanup

This simple science demonstration—sometimes called “oobleck”—creates a fascinating non-Newtonian fluid that acts like both a solid and a liquid depending on how you treat it. It becomes firm and hard when you hit or squeeze it, yet turns back into a smooth liquid when you relax your grip. This unique reaction makes it a perfect illustration of how we respond to God’s will and the power of surrendering to Him.

To prepare, mix one part water with about two parts cornstarch in a clear bowl. Stir slowly until the texture is smooth and thick. When you press your hand quickly into it, it should feel solid. When you lift your hand slowly, it should ooze between your fingers. Add a drop or two of food coloring if you want to make it more visible for your class.

Begin by letting the children explore the substance briefly (if appropriate for your setting). Have them try to punch it or grab a handful. They’ll notice that when they hit or squeeze it, it hardens instantly and resists their efforts. But the moment they stop trying to force it, it melts and flows freely. Explain that this is exactly how we can be with God. When we fight, resist, or try to control everything on our own, our hearts become hard. The more we struggle against God’s plan, the more resistance we feel. But when we surrender—when we stop fighting and simply let Him lead—His Spirit can flow freely in our lives.

You can make this even more powerful by drawing a parallel to prayer and worship. When someone resists God’s Spirit, they might feel frustrated or stuck. But the moment they lift their hands, open their heart, and yield to Him, the Holy Ghost begins to move. Just like the cornstarch loosens under gentle movement, our hearts soften when we allow God’s presence to flow.

End the lesson by emphasizing that God doesn’t want us to be hard and unyielding. He wants us to be moldable, willing, and ready for His touch. When we let go of control and trust Him, His Spirit fills us and brings peace instead of struggle. The same hands that fought the mixture now move gently through it—just like the same heart that once resisted God can now rest in His will.

This lesson is fun, memorable, and deeply spiritual. Kids love the strange behavior of oobleck, but what they’ll remember most is the truth behind it: life works best when we stop fighting and let God flow through us.