Diet Coke Mentos Experiment

My 4-year old and our neighbor enjoyed witnessing this explosive soda and Minty Mentos experiment. Have you tried it? It doen’t require a huge set-up, and the show is pretty awesome. I have to warn you that the explosion itself goes by quickly, so you might want to have an arsenal of soda containers on hand so you can conduct multiple experiments.

diet coke and mentos explosion

Ingredients for Diet Coke and Mentos Experiment

  • Diet Coke
  • Minty Mentos
Hee hee — pretty obvious, huh?

mentos and diet coke

Take the Mentos out of the wrapper.

mentos and diet coke experiment

Almost as soon as the Mentos hit the soda, the explosion begins, so f you’d like to try dropping more than one into the Soda bottle, make a paper tube and fill it with all your Mentos.

filling mentos into a tube

Take it outside. open the bottle, drop in one (or multiple) Mentos, and then step back!

kids mentos and diet coke

The explosion happened so fast that I was unable to capture it with my camera, so you’ll have to try this experiment for yourself and see how it works.

Experiment ideas

  • Try this with other types of soda. I read that diet soda is recommended because it’s less sticky than regular soda, but regular soda should work too. Compare the results of regular and Diet Coke.
  • The carbonation is what’s supposed to trigger the reaction: try this experiment with carbonated water. What happens?
  • Compare the results of fruit-flavored and mint-flavored Mentos.
  • What happens when you add other ingredients to the soda: salt, rock salt, sugar, baking soda, peanuts.

soda science experiment

The Science Bit

According to Wikipedia, “the numerous small pores on the candy’s surface catalyze the release of carbon dioxide(CO2) gas from the soda, resulting in the rapid expulsion of copious quantities of foam”

Taking this 100 Steps Further… (Entertainment for the Curious Mind) shared that  the exploding Diet Coke and Mentos Experiment was first introduced by University of Chicago chemistry professor, Lee Marek. The Eepybirds later recreated this experiment in a spectacular multi-bottle show on David Letterman.

 Your Turn!

So, are you ready to run out and pick up some soda and Mentos? Have you tried this experiment? What did your kids think about it?

Crushed Flower Experiment

Now that summer is coming to an end (sniff — I’m kind of in denial — you?), it’s a good time to harvest some of your last blooms for some flower-painting experiments.

Crushed flower experiment

We took a walk around the neighborhood and picked some weeds from wild roadside gardens, and also selected a handful of flowers and leaves from our own yard.


For this project you’ll need: assorted flowers and leaves and paper

The experiment lies in testing the flowers to see what colors actually emerge from them as they’re crushed and smeared onto paper. We were surprised by the blue hydrangea’s brownish-green hue, but also got some more predictable amazingly brilliant yellows and purples from our roses and dandelions.

Crushed Flower Experiment

More Artsy Science Experiments

If you’re interested in more experiments that lie at the intersection of art and science, you might also enjoy Invisible Ink: A Citrus Painting Experiment and the Egg Geodes Science Experiment.

More Flower Projects

For more with flowers, you’ll have a lot of fun Pounding them into Flower Bookmarks or maybe you want to learn how to press flowers. Zina at Let’s Lasso the Moon has a lovely idea for turning a huge sunflower harvest into back-to-school teacher gifts. And, there are over SIXTY amazing ideas in the Tinkerlab Flower Creative Challenge that will keep you busy with all your harvested flowers.

And similarly, here are some ideas for making vegetable-based egg dyes.

What are your favorite ways to use, preserve, and harvest your end-of-summer flowers?

Invisible Ink: A Citrus Painting Experiment

It’s summer and we’ve been doing a lot of citrus juicing in our home. Between my 4-year old expert juice squeezer and my almost 2-year old juice taster,  our simple and inexpensive juicer has been hard at work.

invisible ink science activity kids

While little Rainbow napped, Nutmeg and I gathered materials and set up the project. We talked about how we’d have to reveal the ink (lime juice) with the high heat of an iron or hair dryer, and she couldn’t wait to get started. She loves dangerous tools.

invisible ink citrus kids

We gathered our ingredients.

Here’s the full recipe:

5.0 from 2 reviews
Invisible Ink: A Citrus Painting Experiment
Recipe type: Science
Prep time:
Making time:
Total time:
Lemon juice is acidic, and acid weakens paper. When paper is heated, the acid burns and turns brown before the paper does.
  • Lemon or Lime Juice
  • Paper
  • Paint brush or Q-tip
  • Iron
  1. Squeeze lemon or lime into a bowl.
  2. Paint the juice onto your paper with a paint brush or Q-tip.
  3. Wait for the paper to dry.
  4. Heat the paper with an iron, hair dryer, light bulb, or other heat source. Be careful that you don't hold it there to long, as it could burn the paper.
Experiment with other liquids: milk, orange juice, white wine, vinegar, and apple juice are good bets.


invisible ink citrus lemon lime kids

Just as we were getting started, baby R woke up to join us. She’s 22 months old now, and enjoyed the sensory experience of squeezing the limes with her bare hands, and then licking her fingers. According to my mom I used to eat lemons right off our tree, so this wasn’t too much of a surprise.

invisible ink lemon lime juice

The girls experimented with different colored papers and brushes. Afterwards I realized that Q-tips would have been perfect for this project, but we enjoyed the challenge of small watercolor brushes.

invisible ink citrus lemon lime kids

The papers dried pretty quickly on this warm day and we were able to get right to the fun part of burning the acid with heat. N’s grandma blows her hair dry every day, and N is obsessed with this tool. Obsessed. We ran the heat on the paper for about a minute with little success. I never blow dry my hair and have a cheap blow dryer for projects like this, and maybe that’s why? In any case, we decided to move on to the iron.

invisible ink citrus lemon lime kids

I folded a thick towel, placed the art on top of it, and she ironed away. In most cases an ironing board would have been better, but ours pulls awkwardly out of the wall and it’s too tricky to get the three of us around it safely. This worked perfectly and only took a few seconds to show its results.

invisible ink citrus lemon lime kids

N’s picture of her and her dad (he’s above her head, slightly visible in all his heated lime acid glory).

invisible ink citrus lemon lime kids

I really like how the abstracted images turned out and wished I had joined them once I saw how cool these looked. I usually join in when we’re creating and somehow forgot to on this round.

How about you? Do you find yourself doing projects with your kids, or are you in more of the facilitator mode? And what do you think about the new recipe card tool and header?

Egg Geodes Experiment

Today we’re experimenting with egg geodes. This experiment is set up to engage children in the steps of the scientific method, which could easily make this a fun and successful science fair project. Not only is the process of making these beautiful geodes engaging for kids, but the end-result has a huge wow-factor. Give yourself at least two-three days to achieve the greatest results.

Egg Geodes Inspiration

I was inspired by these egg geodes that I spotted on Martha Stewart and then followed this recipe by Melissa Howard who blogs at Those Northern Skies. If you enjoy this post, do click over and see what these two sites have to offer. The pictures alone are worth looking at.

egg geodes

Set up the Egg Geodes Experiment


  • Eggs
  • Rock Salt
  • Sea Salt
  • Borax*
  • Other substance that could be tested for crystallization such as sugar, epsom salts, cream of tartar, baking soda, or alum*
  • Mini-muffin pan
  • Food Coloring
* Borax and alum are not food products, and using these ingredients with small children should be closely monitored, as ingestion can be fatal. Please use common sense and close supervision with such substances. My children were watched at all times and did not come in direct contact with borax in the process of this experiment.

clean membranes from eggsI tapped a knife around the top of the eggs to remove a bit of shell, and then emptied the eggs and cleaned them with water. Using a finger, it’s important to gently rub around the inside of the egg to remove the membrane because the membrane can discolor crystals as the form.

If you happen to have a mini-cupcake pan, it’s like they were made for this job.

add salt to water for geodesWe heated a pot of water (not quite boiling) and then poured 1/2 cup into a mug. We added 1/4 cup of kosher salt into the first mug and mixed it until it dissolved.

The kosher salt was stubborn and wouldn’t dissolve, so Nutmeg handed the mug to me for some rigorous mixing. Sill no luck.

We moved on to the next mug: 1/2 cup hot water + 1/4 cup sea salt. The sea salt dissolved quickly and then we added a bit more. The idea is to saturate the solution without putting in too much of the dry ingredient.

And then the final mug: 1/2 cup hot water + 1/4 cup borax. Dissolved.

geode chartWe added a coup;le drops of food coloring to each mug and then made a chart so we wouldn’t lose track.

Then we poured the liquid into our eggs. Each solution made just enough to pour into two eggs. Perfect!

And then you wait. 5  days for the liquid to mostly evaporate.

We couldn’t that long, but after 1 day salt crystals evaporated through the egg shell, and after 2 days our eggs looked like this…

egg geodes

egg geodes

Kosher Salt 

Through the process of diffusion, the salt actually passed through the permeable shell. Gorgeous, isn’t it?

egg geodes

Sea Salt

egg geodes borax


With opposite results of the salt-solutions, borax created the most sparkly, crystal-looking egg with crystals inside the egg and nothing on the outside.

And of course, things like this are irresistible to little hands. My toddler wanted to pick all the crystals off the shells, and I had to pull them away because not only will she break them into a gazillion pieces, but substances like borax are safe for looking, not for touching.

So, if this strikes your fancy, have fun testing some of the different soluble solids mentioned in the list above.

egg week

This is Day #4 of Egg Week, which I’m co-hosting with my talented arts education friend Melissa who runs the popular children’s art blog, The Chocolate Muffin Tree. Take a minute to hop over to The Chocolate Muffin Tree and see the egg surprise she has in store for us today.

And if you’re just catching up with us, here’s a look at what we’ve covered this week so far:


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Are Black Markers Really Black? A Chromatography Lesson.

are black markers really black chromatographyWhat color is black? Is it one color or many colors combined to “look black”?

Black is the absence of all reflective colors, and when the three primary colors (red, yellow, and blue) are combined in just the right way, they give off the appearance of black.

We set off to find out more about the predominant colors in our black Crayola marker, and to do this we had to separate the colors. The chemical technique used to separate dyes, pigments, or colored chemicals is known as chromatography. 

This activity can take anywhere from 5 minutes to 25 minutes, depending on how much experimenting your child wants to do, and it’s appropriate for kids ages 2 and up. It’s so simple to do, and would be a natural addition to a morning or afternoon of drawing with markers.


  • White paper towels or white coffee filters
  • A Plate
  • Black marker/s
  • Water
  • Water Dropper

add water to black ink

We started by drawing a big quarter-sized dot on the paper towel, and then squeezed water on top of it. The colors that are released into the paper towel give you some clues as to what goes in to your black. In our case, there was a lot of green.

add water to marker on paper towel experimentAfter the black marker test, 3-year old N wanted to test the rest of her markers. She made a lot of predictions, and they all came out as expected (yellow appeared to be yellow and green was made from green dyes).

add water to marker on paper towel experiment

The red and pink, however, stumped her as they both released a pink color.

add water to marker on paper towel experiment ChromatographyAnd then there was a lot of fun in opening the paper towels up to reveal the levels of color that soaked through all the layers.

More Chromatography

For older kids, this slightly more advanced version of our kitchen experiment from Science Project Lab has some pretty cool results.

Kids will be amazed at the rainbow of colors released by leaves in this chromatography experiment shared over on TLC Family.

I like this coffee filter chromatography project from Kids Make Things.

Have you tried this experiment with your kids? Do you have a favorite paper towel/coffee filter project? What is the most challenging part of doing experiments with your kids?