Easy Sun Print STEM Activity: The Power of the Sun

If you live in an older house, you may notice that parts of the floor and walls are faded in color. Since my kids were born, we moved 6 times, but we never lived in a house older than two years old until now.

With a house built in the 1980s, you can definitely see the difference in color where furniture was versus areas that were exposed to sunlight. My kids noticed this and asked why the floor has different shades of color.

Sun Print with Coins Removed Paper

Since we just completed the LEGO sundial and our 3D solar system, this is the perfect segue into the power of the sun! 

In this simple experiment, your kids will learn just how potent the sun’s rays are, and why colors fade under the sun.

How to Make Sun Print Art with Coins


  • Construction paper (you pick the color)
  • Coins 
  • Optional: Baking sheet 
  • Optional: Anything that would fit on the construction and wouldn’t melt in the sun


1. Place the construction paper on the baking sheet. You can skip this step if you are doing this outside.

2. Arrange the coins and anything else you have that won’t melt in the sun on the construction paper.

Sun Print with Coins on Baking Tray

3. Leave everything outside in the sun for a couple of hours. Depending on how much sun you get, the time will vary.

Sun Print with Coins in the Sun

4. Bring the paper and the coins inside and observe what happened! Tip: You may want to wear gloves because the baking sheet and the coins will get very hot underneath the sun.

We tried to imitate the shape of the sun with our coins. It was kind of successful. Maybe if you squint your eyes? 

Sun Print with Coins

As you can see, the sun faded the construction paper’s color quite a bit. I do have to note that we live in Arizona so we are under hot, desert sun, so this was the result of leaving the paper outside for 2 hours. It might take longer for your sun art to complete if you leave the paper out on a cloudier day.

The color of the construction paper also causes some variance in the time it takes the color to fade. The colors that fade the fastest are yellow, orange, and red. 

The kids were amazed when we removed the coins and saw how much darker the area underneath the coins was. The coins blocked the paper from the sun’s UV rays, and therefore protected the color from fading.

Why the Sunlight Causes Colors to Fade

Construction paper has color because they contain pigments or dyes. When light shines on pigments or dyes, they absorb only certain wavelengths of visible light while the other wavelengths bounce off the molecules. The color that we see is the reflected light spectrum.

The Sun emits damaging Ultraviolet Radiation, or UV rays. UV light breaks down the chemical bonds in the pigment and dye molecules, making them less effective in absorbing and reflecting light. As a result, the colors appear to have faded.


My husband and I were shocked at how fast the color faded in the sun. This experiment made us more diligent in protecting our skin while we are out in the sun. 

You can do this experiment over and over with different objects. Try using LEGO bricks, eating utensils, or toys to make different shapes and patterns. Just make sure they don’t melt in the sun!

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