Silly (Putty) Science (Grades 3-5)

Have you ever wanted to have super stretchy arms like Mr. Fantastic from the Fantastic Four? This superhero has the power to stretch, bend and re-shape his body just like Silly Putty. 

Hand holding green Silly Putty

If you have ever played with Silly Putty, you know it’s an unusual substance. You can roll it into a ball and bounce it high, or stretch it into rubbery threads. If you build a tall tower out of Silly Putty, it will droop and flatten, and if you hit Silly Putty with something hard, it can shatter! 

This funny substance is a polymer — a chain of molecules. In Silly Putty, the molecules are flexible and can slide past each other. This flexible structure is what lets Silly Putty stretch, flatten, flow and even bounce. Sometimes it behaves like a very thick liquid that can flow, and sometimes it behaves like a soft solid. 

Since liquids behave differently in cold and hot temperatures, this simple experiment will explore how Silly Putty behaves differently when it’s cold or hot. (You can even make your own Silly Putty at home.) 

Silly Putty Bounce Test

Roll your Silly Putty into a ball and push it gently off the edge of a level surface, such as a counter or table. Note how high it bounces — is it higher than the table? How much higher? Repeat this experiment a few times so you have a good idea of how high it can bounce. 

What’s your hypothesis? 

Place your ball of Silly Putty in the freezer for about an hour. Write down what you think will happen when you bounce the frozen Silly Putty ball. Will it bounce higher or lower? By how much? 

Repeat the test and find out if you were right! Share what you found out by tagging #CapRegSummer or emailing