If you’re looking for an easy experiment to do with your kids for Halloween, this simple floating spider experiment definitely fits the bill! You’ll only need a few simple supplies to do this spooky floating ink trick at home.
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Have you ever made dry erase drawings float in water?
This super simple science experiment is perfect for toddlers, preschoolers and school-aged kids—and it only requires a few simple supplies that you probably already have at home.
Read on to find out how you can amaze your children by making DIY floating spiders for Halloween. Our kids love this easy experiment, and I’m sure yours will, too!
How Does the Dry Erase Marker Experiment Work?
Unlike permanent marker ink, which contains an acrylic polymer that makes it stick to the surface it’s on, dry erase markers contain an oily silicone polymer that makes their ink “slippery”.
For this reason, drawings made using dry erase markers do not stick to the surface they’re on, which makes them easy to erase them from whiteboards—or from other non-porous surfaces, like spoons.
Because the ink is “slippery” and doesn’t dissolve in water, the water is able to slip underneath the drawing and detach it from the spoon. And because the ink is less dense than the water, it will stay on its surface and begin to float!
How to Make Floating Dry Erase Spiders
Here’s what you’ll need in order to create dancing spiders that float around in water:
- Black dry erase marker (e.g. Expo)
- Small container or dish
- Tap water
- Paper and pencil (optional)
Note: This experiment will work best will new whiteboard markers. The older and more dried out your markers are, the more likely the experiment will fail.
(Having trouble getting this floating ink experiment work? Read to the end of the article for some troubleshooting tips!)
1. Draw Spider on Back of Spoon
Grab your dry erase marker and use it to draw a spider on the back of a spoon.
Make sure that the lines are nice and thick, and that all of the legs are properly connected to the body, or the spider may come apart when when you try to make it float.
2. Let Ink Dry for 10-30 Seconds
This experiment works best when you let the spiders dry just a little—but not too much—before you submerge the spoon in water.
That being said, the exact time that you’ll need to let the ink dry will vary depending on the brand of whiteboard marker you use, and on how dried out each individual marker is.
The Expo marker I used worked best when I let the ink dry for about 15-30 seconds, but you may need to let yours dry for a different amount of time. You’ll probably need to experiment a bit to figure out what works best for you.
3. Place Spoon in Water
This is where the magic happens!
Fill a shallow dish with water (I used a square casserole dish) and, holding your spoon at an angle, gently drop your spoon into the water to see if the spider’s legs begin to peel off the spoon.
If the spider doesn’t peel off, try inserting the spoon at a different angle to see if that helps.
If not, your shape is probably either too dry, or not dry enough. Erase the spider, thoroughly dry off the spoon and try again, letting the ink dry for a different amount of time to see if it works better.
If the spider does start to peel off, gently rotate your spoon to help it along.
Keep doing this, gently tilting and rotating your spoon as needed until the spider detaches itself completely. This may take a bit of practice the first time you do it, but you should get the hang of it pretty quickly.
Once the spider has completely peeled off, quickly remove your spoon from the water to prevent the spider from latching onto its surface again.
4. Repeat Previous Steps
Using the same shallow dish, repeat the three previous steps as many times as you like to create more floating spiders. The more spiders you add, the cooler it will look!
5. Catch Floating Spiders (Optional)
This last step is totally optional, but my kids really enjoy it.
To “catch” the floating spiders, simply cut a sheet of regular white printer paper into small pieces. For added fun, I drew a spiderweb on ours using a pencil.
Then, place each piece of paper on top of a floating spider and watch as the dry erase shape sticks to the paper!
(Note: This can also be a good way to clean up your dish partway through the experiment if any of the spiders have broken apart.)
Help! My Dry Erase Experiment Is Not Working!
There are several reasons why this experiment may not be working for you. The most common reasons are:
1. Your marker is too dried out: This experiment works better with dry erase markers that are new or haven’t been used much. Try repeating the same steps with a newer marker to see if that works better.
2. The ink is too dry or not dry enough: For best results, you’ll need to let the spiders dry a little bit before you try to place it in the water—but the ideal drying time may vary. If you think this may be the issue, try experimenting with different lengths of time to see if you can get it to work better.
If neither of those fixes work, you can also try drawing the spiders directly onto the bottom of a dish or plate, and slowly pouring the water into the corner until it covers the bottom.
If you have allowed the spiders sufficient time to dry, the water you add should be able slip underneath the drawings and lift them off the bottom of the dish!
Related Science Experiments for Kids
Looking for more simple science activities for kids? Check out these articles:
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