When you hear the word “chemistry” you probably think of a science lab, factory, or other formal scientific environment. But really, chemistry—the study of the what substances are made of and how they interact—is all around us. If you’ve ever made slime, baked a brownie, or washed your hands with soap, you’ve used chemistry. What does chemistry have to do with art? It is used to make paints and pigments, and it controls the way that different substances interact. That leads us to our STEAM Week art project: Shrinky Dinks!

What is a Shrinky Dink? It’s a piece of plastic (#6 or polystyrene, to be exact) that you can cut, color, and make into whatever creation you want. You can make jewelry, a bookmark, a keychain, a sun-catcher, a mobile, or whatever you can imagine! When you’ve got your design perfected, you heat the plastic and it shrinks to about 1/3 its original size. The end result is something hard and durable.

People who get really into creating Shrinky-Dinks often use special “paper” purchased at an arts and craft store. However, you can use materials you may already have around the house! You might see #6 plastic in the clear plastic containers restaurants use for takeout, clear plastic cups, or in old CD jewel cases. Not any old plastic will do, though. Each type of plastic, from #1-7, has its own unique properties.

What you’ll need:

  • polystyrene #6 plastic (limited quantities available with the Teen Crafts Pick-Up 7/16)
  • felt tip/permanent markers, colored pencils, or gloss acrylic craft paint with brush
  • scissors (and maybe a hole-punch, depending on your design)
  • piece of cardboard or parchment paper
  • baking pan
  • oven
  • a grown-up to help supervise

Step 1: Get Creative

Use your markers, colored pencils, or paint to make a design on one side of the plastic. I like using permanent markers, but you should use whatever you (and your adult) are comfortable with. When you’ve finished coloring, cut around the edges of your design to trim off the extra plastic. If you’re making something that needs a hole, like a necklace or a tasseled bookmark, punch the hole now.

Remember: Shrinky Dinks really shrink! The finished size of your project will be approximately 1/3 the size it is while you’re decorating.

Need a little design inspiration? We have a printable PDF with some design ideas you can trace.

We decided to make a rainbow mobile. We’ll hang raindrops from each of our clouds. If you plan to connect pieces together, remember to place any holes BEFORE you bake!

Step 2: Get Hot!

Have your grown-up help you with the oven. Pre-heat the oven to 325 degrees Fahrenheit. Place the cardboard or parchment paper on the baking sheet. Place the Shrinky Dink on the covered baking sheet, decorated side up. Once the oven is at the correct temperature, place the baking sheet inside. (If you have an oven light, be sure to turn it on! You can watch the shrinking happen!)

The plastic is going to look like it’s doing nothing, then it will shrink one one side, then another, until the edges start to curl. Pretty soon the whole thing will curl up tightly, and it may even fall over to one side. This is normal! As the Shrinky Dink continues to bake, the edges will lay back down again.

The whole process should take only 1-3 minutes, depending upon the size of your design. After it lays flat again, bake for another 30 seconds or so before you or your grown-up (carefully!) remove it from the oven.

Use the cardboard or parchment paper to lift the shrunken Shrinky Dink off of the baking pan. Allow it to cool thoroughly before handling—if you pick up a Shrinky Dink too soon, you can accidentally bend it.

Step 3: Finishing Touches

Depending upon your design you could be all finished after Step 2. If you punched a hole in your design to thread a string through, now’s the time to do it! If you have rough edges that you’d like to be rid of, you can gently sand your creation (I like using a nail file). You can glue things to your Shrinky Dinks, hang them on hooks, string them together in a chain—your imagination is the limit!

We used embroidery floss to string our raindrops to our rainbow, using the holes we punched before baking.

To read more about the science of Shrinky Dinks, check out this article from Smithsonian Magazine.