Pencil In Water Bag Experiment ~ Nifty Thrifty DIYer

Last updated on September 28th, 2024 at 05:02 pm

Happy weekend friends! I hope you’re soaking up the last bit of summer with some fun and sunshine. As summer winds down, if you’re on the lookout for a quick, easy, and fun activity for the kids then you’ve come to the right place. In our home science experiments are a huge hit —I mean, who doesn’t love a good “WOW” moment? I love watching kids eyes light up when they see science in action. And this Pencil In Water Bag Experiment definitely delivers that reaction.

If you’ve never heard of the pencil in water experiment, you’re in for a treat. It’s a super simple experiment to put together with just a couple supplies that you probably already have on hand. With just a plastic baggie, some water, and a few pencils, you can create a “WOW” moment that seems to defy logic—no matter how simple the experiment, kids and grown-ups can’t help but be amazed! Plus, it’s mess-free and perfect for those moments when you need something quick and engaging.

We’ve tried our share of science experiments over the years, and some favorites have been the Skittles Rainbow Experiment, the Baking Soda and Vinegar Balloon Experiment, and the Magic Milk Experiment (this one’s a top pick around here!). There’s just something about hands-on learning that sticks with kids—and who says learning can’t be tons of fun too?

So, if you’re ready to add some fun science to your day and create lasting memories with the kids, let’s dive in! Gather your supplies, round up the kiddos, and get ready to see the amazement on their faces—let’s get started!

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Pencil In Water Bag Experiment

What You’ll Need

What To Do

Step 1

Prepare your pencils by making sure they are really sharp. This is ‘a must’ for being able to poke through the plastic baggie.

double photo: sharpening pencil, showing sharp point of sharpened pencil

Step 2

Fill your Ziploc sandwich bag almost to the top with water and seal it tightly. It’s a good idea to do this over the sink—things can get a bit tricky if the bag is too full when you’re trying to zip it closed!

Step 3

Using the sharp point, poke the pencils through the baggie of water. Continue with the rest of the pencils. We used about 6-7 pencils.

The Science Behind The Experiment

When you poke a sharp pencil through a plastic bag filled with water, you’d think the water would leak out, right? But it doesn’t—how cool is that?

Here’s Why:

The plastic bag is made from a material called polyethylene, which is stretchy and has long chains of molecules. When you push the pencil through the bag, those stretchy molecules squeeze tightly around the pencil, sealing it and stopping the water from leaking out.

It’s almost like the bag gives the pencil a big hug! The water stays inside because the plastic seals around the holes, keeping everything in place. So even though it looks like magic, it’s really just some clever science at work! Isn’t science awesome?!

Get Creative: Use Pencil Crayons for a Bright, Colorful Experiment!

Who says you just have to use plain pencils? Why not try bright, colorful pencil crayons. Let the kids choose their favorite colors to poke through the baggie.