Today we’re doing a water illusion! Kids of all ages will love this upside-down smile illusion that just uses a few craft supplies. This water illusion will seem like magic, but there is actually some science behind it making it fun, magical, and educational! Do this upside-down smile illusion at home or in the classroom and wow everyone!

Water Illusion
This upside down smile illusion will have you scratching your head! The paper has a smiley face, but when you look at it behind the water, suddenly it’s frowning?! How does that happen? It’s science!
Turns out water and light can distort images and create funny effects on things and this water illusion shows just that! Older kids and younger kids alike will be able to see how the paper changes and learn why this happens! But first, let’s set up the experiment.
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Related: Download and print our scientific method steps for kids printable!
Supplies Needed For This Water Illusion
Step 1
Fill your jar with water and put the lid on it.
Step 2
Draw a smiley face on your piece of paper. Make it kind of thick so you can see it well.

Step 3
Put the mouth of your smiley face behind the glass of water. What do you think will happen?
Step 4

Observe how the smiley face is now a frowny face. Super cool, right! But why does it do that?
What Causes The Upside-Down Smile Illusion?
The water in the jar acts like a lens. It bends the light and alters the reflection. This causes images to distort making them look funny or even strange. It is similar to the Thatcher illusion where features appear normal when inverted, but super weird when view upright.
To explain it a little better… Refraction is when light bends as it passes through something, in this case water. When you look at the smiley face through the water, the rays of light from the picture bend. This is because of the curved shape of the jar. The image flips horizontally and left becomes right and right becomes left.

When you draw a smile with the corners of the mouth being up, the glass bends the light and flips the smile. So, the corners of the smile are now down, and it looks like a frown!
This science experiment or water illusion is a great way to see how light works. This water illusion shows us that things aren’t always what it seems. Especially when you add light and water!
Water Illusions: Make A Smile Into A Frown With Science

Using a few items you can easily make this water illusion to wow all your friends. You can turn a smile upside and make the smiley face sad using water!
Materials
- Paper
- Marker
- Jar
- Water
Instructions
- Fill your jar with water and put the lid on it.
- Draw a smiley face on your piece of paper. Make it kind of thick so you can see it well.
- Put the mouth of your smiley face behind the glass of water. What do you think will happen?
- Observe how the smiley face is now a frowny face. Super cool, right! But why does it do that?
More Science Experiments From Kids Activities Blog
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- Why not try these gross science experiments too?
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How did your water illusion turn out? Was it super cool?
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