15 Backyard Science Experiments for Kids

Painting Pendulum

Here's a physics and an art lesson in one fun activity! Kids will learn about the forces of gravity and motion by designing a pendulum that can paint. Use watered-down craft paint and capture your art on paper, or mix your own sidewalk chalk paint and make swirled masterpieces on your driveway. Innovation Kids Lab has easy instructions. 

Insider tip: while you're outside on the sidewalk, check out these great sidewalk kids science experiments for serious non-stop fun. 

Make Your Own Bouncy Balls

A little glue, some corn starch and borax powder are all you'll need to make bouncy balls worthy of a gumball machine. Kids will have almost as much fun playing with these balls as they do making them. Get the simple instructions at Kids Activities Blog—or, if you only have clear glue, find an alternate recipe here.

Make Elephant Toothpaste

This is one of those oldies but goodies the kids will want to do again and again (so stock up on hydrogen peroxide and yeast now). This one guarantees a fun, foamy chemical reaction—with just a few simple steps. Scientific American has a great tutorial here. 

Make Simple Explosions

Looking for a science experiment with a little POP? This easy science project takes cues from the vinegar-and-baking-soda bandwagon but does so with a bang. Get the easy steps for (harmless) explosive action at Science Bob (There's a great video to watch here, too.). 

Floating Beach Balls

Kids may not fully understand what Bernoulli's Principle is, but they'll love seeing it in action as they watch a beach ball "magically" floating above a leaf blower—even at an angle! Get the instructions (and other fun leaf-blower experiments) at Fizzics Education.

Make Flowers Change Color

Use white flowers from your garden to set up this experiment that demonstrates the capillary action in plants. The simple secret to making this invisible process visible is food coloring. Get the full rundown here, along with other kids science experiments to try!

See Photosynthesis in Action

It’s the things that kids can’t see that make science so exciting, and also a little confusing. That’s why we love this surprisingly simple experiment from Edventures with Kids. With a few supplies and a bit of wait time, your budding botanist can “see” photosynthesis in action.

Hole-y Cow

Before you start this experiment, have your scientific sidekick predict what will happen when she starts pushing pencils through a water-filled bag. She’ll have the chance to (literally) poke holes in her own theory once she gives it a try, thanks to the polymer chains that keep the plastic from leaking. Get the important details to set up at Steve Spangler Science.

Make a Sun Dial

Unravel the mysteries of time. Or at least figure out the basics by setting up a sundial outside. Take time each hour to check the sun’s positioning and make note of it so your sidekick can see the bigger picture.

Wingardium Leviosa

The (air) pressure’s on in this sweet science experiment that lets your kids levitate water over an unsuspecting friend’s … or better yet, a deserving sibling’s head. To try it at home, follow these easy instructions from Steve Spangler Science, and keep a towel at the ready … just to be on the safe side!

Balloon Rockets

Erica at What Do We Do All Day proves once again that science doesn’t have to be boring with this exciting experiment that’s a study in propulsion as much as it is a fast-paced racing game. Use her helpful suggestions to really delve into (and add scientific challenges to) this project. Get ready, get set, go! 

DIY Tide Pools

The ebb and flow of ocean waters is the focus of this experiment designed by Chelsey at Buggy and Buddy. Find out how to set up the microcosmic world in your backyard, using a few easy-to-find supplies. Then let your budding oceanographer have at it. 

Let the Sun Do the Painting

You gotta love a two-fer! Our current fave is this gorgeous art project from Rachelle at Tinkerlab that doubles as a science experiment. All it takes is a little sunlight and artistic vision to give this one a try!

Make Simple Machines

How far? How high? And how many? These are just a few of the questions your budding physicist will be able to answer after he builds a simple lever machine. Find out how to put it all together and design easy experiments at Buggy and Buddy. Who knew snow in the summer could be so fun?

Keep Paper Dry in Water

This sweet experiment will leave your Little wondering how the paper towel stayed dry … even after she dunks it in water. Psst … the secret’s in the air trapped inside the cup, but don’t take our word for it. Get the low down on how to run the experiment yourself at Simple Play Ideas.