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Science Experiments That Are 100% Worth The Mess

Make your backyard or sidewalk into a gloriously messy mad scientist's laboratory!

Margo Gothelf and Sarah Burns

backyard science experiments

Getty

Typically, making a mess isn't exactly a good thing. But with these at-home science experiments, it's highly encouraged! From fizzing and explosions to gooey textures and slimy blobs, it's all here for your kids to mess around with. So roll up their sleeves, grab a pair of safety goggles, turn their lab coat into a smock, and get ready to get messy! 

Fizzy Sidewalk Chalk Paint

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Messy Little Monsters

Drawing with chalk on the sidewalk during the summer is a tradition as old as time. This year, change it up and learn how you can turn your kid's chalk into fizzy paint with this simple experiment. Head on over to Messy Little Monsters and make homemade chalk paint with the kids in different colors, then they can bring the paint mixtures outside and channel their inner artist. After they've created their artistic masterpiece, it’s time to watch it fizz! Have them spray the chalk paint with vinegar and watch their artwork come alive.

Elephant Toothpaste

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Teach Beside Me

Full disclosure: your kid won’t get to see a real-life elephant as part of this experiment. But they’ll understand why it's called elephant toothpaste by the time the experiment is over. Help them combine the ingredients as listed over on Teach Beside Me and watch the chemicals go to work. The chemical reaction will cause the liquids to foam and explode, sort of resembling a giant tube of toothpaste — kinda like the kind an elephant would brush its tusks with? Have them try this one out using different colors of food coloring in a few different jars and set them off at the same time to see which one will jump the highest!

Magic Milk

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Living Life and Learning

Make their milk move like a kaleidoscope. All they need is a little dish soap, food coloring, and cotton swabs to make it twist and turn. The different substances react to form one-of-a-kind designs and abstract patterns, just like they would see out of a kaleidoscope. This simple trick involves a little bit of science, art, and magic. Check out the details and find out all of the science behind the fun patterns over on Living Life and Learning.

Rainbow Melting Ice

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The Artful Parent

This colorful melting ice experiment is the perfect activity for a hot summer day. The night before, have the kids fill up some different-sized containers with water and set them to freeze overnight. The next day, have them head outside and place the salt all over the ice and watch the chemical reaction come to life. As the salt starts to melt the water, add in the food coloring for a rainbow waterfall. It will quickly turn their block of ice into a colorful, melty mess. 

Baking Soda and Vinegar Fireworks

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STEAM Powered Family

Taken on their own, baking soda and vinegar are pretty boring. But when the two substances come together, things get quite literally explosive! Let the kids see for themselves with this bubbling firework experiment. Combine the two substances together with a little bit of glitter to create a personalized firework show. Save this one for the 4th of July for holiday-themed science hijinks. Get all of the details over on STEAM Powered Family

Erupting Lemon Volcano

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Little Bins for Little Hands

Show them how to turn a lemon into a volcano! Little Bins For Little Hands will show them exactly how to do that with just some simple household items. So how do they get the big explosion? It’s all about the chemical reactions between the baking soda and a lemon. The baking soda creates carbon dioxide once it hits the lemon, causing a bubbling and messy reaction. Encourage them to see if other citrus fruits do the same thing and try out the same experiment with limes or grapefruits! 

Rainbow Pop and Mentos Experiment

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Living Life and Learning

Take the Coke and Mentos experiment up a notch by adding in a pop of color! To get the dazzling rainbow effect, have the kids replace the classic cola with different flavors of Fanta soda. The soda will have the same reaction as the cola but will produce a super colorful explosion. Don’t even bother trying this one inside — unless you want to clean soda off your ceiling! Find all of the details and science behind the reaction over on Living Life and Learning’s site.

Exploding Paint Bombs Activity

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Kids Activities Blog

Are your kids tired of painting with just a basic paintbrush? Add a little science experiment into their art projects with these exploding paint bombs. So, what exactly are paint bombs? They're film canisters filled with water-based paint and Alka-Seltzer tablets. The tablets react with the paint and build up pressure to blow the tops off of the canisters. The results? A mind-blowing design! All they have to do is fill the canisters, close the tops and watch the science create art in real-time.

Exploding Baggies

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Kids Activities Blog

Whenever baking soda and vinegar combine, chaos ensues, especially in this exploding bag experiment. Have kids fill a plastic bag with vinegar (with food coloring if they want it to be a colorful explosion) and tie it shut with a clothespin. In the remaining space, have them add in some baking soda and tie the bag shut. Then, help them to quickly remove the clothespin, and take cover! Watch as the two substances come together to pop the bag — it won’t matter how tight they sealed it, the reaction will make it burst!

Oobleck

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Unsophisticook

If you’re new to oobleck, get ready for it to become your kid's new favorite messy activity. Oobleck is a combo between slime and putty. It’s gooey, oozy, and somehow a liquid and a solid all at the same time. Also, it’s pretty easy to make — all your kid needs to make it is cornstarch and water. Head on over to Unsophisticook to see how to whip up a batch and learn all about the non-Newtonian fluid.

Bouncing Bubbles

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A Little Pinch of Perfect

Bubbles are fun no matter how old you are. The only issue? They have a super short lifespan and pop pretty quickly. Thankfully, with a little scientific trick, your kids can make them last a whole lot longer: Instead of blowing bubbles with a premade mix, help them make their own with soap, water, and a little bit of sugar. The mixture creates a strong reaction causing the materials to bond together, making the bubbles extra durable. With this mixture, they’ll be able to bounce the bubbles and hold them in their hands. They'll have to wear gloves to make it work since the oils in their hands will break down the substance, but it will be worth it! 

DIY Crystal Landscapes

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Babble Dabble Do

The hottest ticket in town this summer will be the growing crystal show in your kid's backyard — good thing they've got front-row seats! They'll spend four days this summer watching magic happen before their eyes with the crystal growing experiment from Babble Dabble Do. The multi-day science project shows how a random crop of ingredients can form to make super shiny and beautiful crystals. Make sure they pick a block of days with good weather where they can watch the experiment at work, as they won't want to miss this science happening in real time.

Frozen Goop

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Babble Dabble Do

Forget cooling off with a refreshing drink or a dip in the pool. This summer, help the kids cool down with frozen goop! Frozen what now? Frozen goop! Frozen goop takes the classic recipe for oobleck and adds another layer of mystery into the part-liquid, part-solid substance by freezing it. As the goop melts, it reverts back into its original form...whatever that may be. Have your kid give it a try for themselves, and check out Babble Dabble Do's site for all of the details.

Rubberized Eggs

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Little Bins for Little Hands

Order up! Today's menu includes scrambled eggs, over-easy, and...rubber eggs! Unlike scrambled eggs or over-easy, the kids will have to wait a whole week for the rubber egg to fully form. Want to know the secret for getting the egg to bounce? It's all in the vinegar. The liquid breaks down the shell and turns it into a consistency that they've never seen before. It's the one time playing with your food is more than okay! Break down the full process and more on Little Bins For Little Hands.

Magic Balloons

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Playdough to Plato

Blowing up balloons with regular air is so last year. The new trend is all about blowing up balloons with anything but air — or at least in the traditional sense. Help your kid see which method works best to blow up a balloon with the magic balloon experiment from Playdough to Plato. The exciting experiment tests out all kinds of materials, including yeast, Pop Rocks, Coke, baking soda, and vinegar, to see which one will make the balloon fill up first. After this, they'll never want to blow up a balloon the traditional way again.

Updated June 2022