Halloween Oobleck

My kids get insanely excited about Halloween, so I need ways to funnel that energy, and provide fantastic sensory experiences. This Halloween Oobleck recipe fits the bill perfectly! The kids played with it for hours and have already asked many times for us to do this Halloween oobleck science lesson again.

HALLOWEEN OOBLECK SCIENCE

Halloween oobleck recipe with spiders, science and a great Halloween party game

It’s no secret, we really enjoy oobleck. It not only provides some incredible sensory experiences, but it also acts as a fine motor strengthening activity, while teaching kids some fascinating science. No matter how you look at it, Oobleck is a win!

As we prepare for Halloween, I wanted to try some new things with our beloved oobleck. We had a few spiders left over from making Spider Soaps and quickly we had our plan! The result was this fascinating Halloween Oobleck that kept the kids mesmerized and really working those fingers!

Halloween oobleck recipe

HALLOWEEN OOBLECK RECIPE

This recipe makes one big batch of oobleck in a large bowl. We wanted to go big with this one and really get in there and explore this non-Newtonian fluid.

Ingredients

Cornstarch
Water
Orange Gel Food Coloring

Supplies

Large Bowl (ours has spiders on it!)
Spoon
Measuring Cup
Spiders
Fake Spider Webs
Skull cups
Covering for your table and floor (Oobleck gets messy, prepare your space!)
Hand towel (I always have a hand towel beside the Oobleck so the kids can wipe their hands as soon as they are done playing)

Halloween oobleck science and sensory fun

MAKING HALLOWEEN OOBLECK

I totally goofed when I made this batch and it made the creation process so much more difficult! So I will share what I did, and then how to do it properly. Learn from my mistakes!

The proper technique is to add 4 cups of cornstarch to your bowl. Then add 2 cups of water that have been coloured with the orange gel food colouring. Mix well.

Pro Tip!  Colour the water BEFORE you add it to the cornstarch. Not after.

See I mixed my water and cornstarch then added the gel food colouring. The problem is that you can’t mix or stir oobleck. It becomes solid under pressure. So I had to keep breaking it up into chunks, then letting it liquify, then breaking it into chunks, then letting it liquify. It took forever to get it all mixed together and get my nice solid orange colour.

It did look kind of pretty though streaking and swirling. Gave me some ideas for future oobleck experiments!

Next add your spiders and skull cups.

Halloween Oobleck with spiders

PLAYING WITH NON-NEWTONIAN FLUID

At this point I had the kids play with our Halloween Oobleck. They tried pulling spiders from the Oobleck. Then attempted to scoop with the cups (hint: it is incredibly hard, when we say Oobleck goes solid under pressure, it is really solid!).

The kids had a blast playing with the Oobleck and exploring how it changed from solid to liquid.

As they played we talked about Newton’s Laws of Fluid Dynamics and how Oobleck breaks these rules. We discussed how the behaviour of fluids is influenced by both density and viscosity. It was great talking about these complicated science lessons in a way that felt natural and real. All while playing and having fun.

Then it was time to explore something new. We decided to add a fake spider web to our Halloween Oobleck to see how it affected the non-Newtonian Fluid qualities of Oobleck. The kids also placed a spider on the web just for fun, but then made an interesting discovery.

Spider Oobleck with webs

FAKE SPIDER WEBS AND OOBLECK SCIENCE EXPERIMENT

At the beginning our spider web just sat on top of the Oobleck doing nothing really.

Then the kids added a spider. It sat on top of the spider web, just kind of hanging out. So the kids pushed the spider down into the web and the Oobleck. It sank down, but as soon as they released their finger it slowly popped back up!

Fascinating Oobleck with spiders and webs

They did this a number of times, completely fascinated.

Then it was time to push the spider web in and explore how the spider web would affect our non-Newtonian fluid properties.

Spider webs in non-Newtonian Fluid

It was fascinating to see how the Oobleck would become solid, clinging to the web as the kids pulled it out, then slowly liquify and run back into the bowl.

Oobleck with spider webs
Oobleck with spider webs in a spider Halloween oobleck recipe

In retrospect I should have asked the kids for a hypothesis and set up our conversation as a full scientific investigation, but sometimes you just need to have fun and let the scientific discoveries happen organically.

Trust me, when the kids saw what happened the smiles and giggles and wide-eyed wonder was exactly the kind of reaction I love to see when doing science! We can save the worksheet and formalities for later.

More Fun Oobleck Ideas

Want to know more about the science behind Oobleck? Check out our Colour Changing Oobleck Science Fair Project for lots of mind-blowing science!

We were having so much fun, I forgot to get video! But you can check out our video of Glow in the Dark Oobleck in action here:

GLOW IN THE DARK OOBLECK VIDEO

HALLOWEEN OOBLECK RECIPE & ACTIVITY

This Oobleck is perfect for a fall science lesson or could be used at a party. Finding items in the Oobleck and getting them out, is a big challenge. My kids are always surprised how much finger strength it takes to extract items from Oobleck. It looks all liquid and easy, but the second you try and pinch, pull or push, it’s solid like a wall.

So instead of bobbing for apples this Halloween, why not have kids “Search for Spiders” in Halloween Oobleck?

It’s a game and science!

Oobleck Halloween Party Game

Just remember never put Oobleck down the drain, as it can clog the pipes. When you are done scrape it into the garbage.

Happy Halloween!

Halloween oobleck recipe with science lesson and a fun Halloween Party Game