Spooky Spiderweb Slime

This spider web slime is a Halloween slime for kids made from white glue, water, instant snow, and slime activator, and it pulls apart into thin, lacy strands that look like a real web.

 

Materials you’ll need

• plastic container
• borax (ask a grown-up to handle this)
• white school glue
• water
• whisk
• instant snow powder (ask a grown-up to handle this)
• spoon
• slime activator (ask a grown-up to handle this)
• measuring cups and spoons
• plastic spiders

⚠️ Warning: Grown-ups only on the borax, the activator, and the instant snow powder. Work at a covered table, keep the powders away from faces so no one breathes in the dust or gets it in their eyes, and wear gloves while mixing the borax if you have them. If skin turns red, itchy, or sore, stop playing and wash hands. Never eat the slime, the snow, or the activator, and keep the borax box out of reach of kids. Wash hands when you’re done, and store the slime in an airtight container.

Step-by-step tutorial

Step 1: Have a grown-up stir 1 teaspoon of borax into 1 cup of warm water until it dissolves. This is your slime activator. Contact solution can work as an activator too, but results may vary.

Step 2: Pour 1/4 cup of white glue and 1/2 cup of water into a plastic container. Whisk until it’s smooth and milky.

Step 3: Have a grown-up add 1 tablespoon of instant snow, then stir it in with a spoon. The mix turns thick and fluffy fast.

Step 4: Have a grown-up add 2 tablespoons of the activator. Stir, and use the back of the spoon to press the mixture together until it starts to clump.

Step 5: Scoop out your instant snow slime and knead it with your hands until it’s smooth.

Step 6: Put the slime back in the container and let it sit for 3 hours.

Step 7: Pull the slime apart slowly and watch it stretch into lacy, web-like strands. Then press a few plastic spiders into the top and stretch it again to catch them in your web.

Learn more

This slime science experiment is all about polymers, which are super long, chain-like molecules. White glue is full of them, and the borax activator adds borate ions that hook the chains together in a process called cross-linking. Linked-up chains can’t slide past each other as easily, so runny glue turns into stretchy slime that still holds lots of water. Instant snow is a polymer too, called sodium polyacrylate, and it soaks up many times its own weight in water and swells into soft, snowy bits. Those bits spread all through your slime and help it pull apart into thin, lacy strands when you stretch it.

If your web needs a spider that moves, Motion-Sensing Spider lets kids wire up a motor, a sensor, and a spring so their spider drops down on whoever walks by.