# Making Sun Prints

Here's your nightly math! Just 5 quick minutes of number fun for kids and parents at home. Read a cool fun fact, followed by math riddles at different levels so everyone can jump in. Your kids will love you for it.

# Making Sun Prints

July 28, 2014

As we approach the halfway point of summer, we can certainly feel one effect of the sun’s energy: its warmth. Yes, after a mild start to our summer, we’re starting to sweat! Did you know there’s another fun and beautiful way to see the effects of the sun’s energy? We’re going to use the sun as a big photo developer in the sky by making sun prints!

## Making Sun Prints

There are two ways to make sun prints: you can either use chemically treated paper especially for making sun prints (available in kits online or in many art and hobby stores) or you can use dark construction paper.

Spend some time gathering fun and interesting objects to print. There are so many different directions you can go with this part of the activity! Here are just a few ideas:

• Nature-inspired items. Even a short walk around the yard can provide lots of materials with interesting shapes and patterns. Observe some of the items you find on your nature-gathering walk. Do you find lots of symmetry in nature? Can you find any examples of Fibonacci spirals?
• Experiment with a variety of solid objects. Find items that are opaque (you can’t see through them), others translucent (they let some light through), and a few transparent ones (you can see through them), too. A button from each category would be ideal.
• Look for objects that will make interesting patterns. For example, find three maple leaves in various sizes. Or how about pebble-leaf-pebble-leaf?
• Geometric shapes. Give the kids a list of common shapes and have them go on a scavenger hunt around the house for small objects that match the shape. You can also cut shapes out of card stock or cardboard. Play with arranging the shapes in different ways. What happens when put two squares side by side? What do you get when you put the base of two triangles together?
• Coins can make interesting designs and patterns, and are easy for younger children to manipulate. Ask the kids to sort the coins before they begin. For older kids, have them calculate how much their design is “worth” when they are done arranging the coins on the paper.

## Let There Be Light

After you’ve chosen your materials, arrange them on the paper indoors and away from direct light. To make transport easy, use a piece of sturdy cardboard under your paper. Once you have your objects arranged in a way you like, take your sun print outside and place it in direct sunlight. If you’re using mostly flat objects, it helps to have a piece of acrylic to cover the items. Not only does it help to keep the objects from blowing away, it also keeps sunlight from creeping under the objects.

If you’re using special solar paper, you only need to wait 2-5 minutes for your print to develop (it can take up to 20 minutes on cloudy days). If you’re using construction paper, it will take much longer, depending on the sun’s rays. In this case, begin checking your prints after an hour to see how they’re “developing.”

While you’re waiting for your prints to develop, try a few other sunny activities. Based on how sunny or cloudy it is, have the kids estimate what your exposure times will be. Talk about how the sun changes throughout the day and observe the sun’s patterns in your yard. What direction does the sun move throughout the day? When is it the brightest? Where are the sunniest spots in your yard? You can even make your own sundial! Or do a sunny Bedtime Math problem!

While we’re used to feeling the sun’s energy at work, sun prints give us a chance to see the power of that energy though the sun’s light.

We often hear about ultraviolet (UV) light, especially in the summer as we think about spending our days at the beach or the pool. UV light is a short wavelength of light that the sun produces that can be very harmful for living creatures. It’s the cause of sunburns and can even be used to kill germs.

In the case of sun prints, the UV light from the sun is causing a chemical reaction in the paper. The parts of the paper that are exposed to the UV light change color, while the parts covered with objects are unaffected. If the kids balk about the hassle of applying sunscreen, this is a great lesson in what a difference being covered can make to your delicate skin!

We’d love to see your sun prints! Share photos of your creations with us on the Bedtime Math Facebook page, or share them on Instagram and tag us (we’re @BedtimeMath). We can’t wait to see them!

Photos courtesy of Angie Six