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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In case you blinked and missed it, TinkerLab rounds up all the great stuff on the internets on keeping you and your critters creative and wraps it up for you in a tidy newsletter! (And throws in some secret giveaways for good measure!)  – Yuliya P., San Francisco, CA

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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?

Magical Plastic Bag Experiment

Polymer Science Project for Kids that Feels like Magic. So simple. Easy to do at home. via TinkerLab

Here’s a fun experiment that won’t take a lot of time, and it’s more than likely that you have all the “ingredients” around the house. I did this with my three and a half year old, and it would be relevant for preschoolers and elementary-age children.

The idea that we’re testing here is what will happen if we poke a sharp pencil through a plastic bag of water. Will the water leak through the holes? Will the water spill out? Or will the bag reseal around the pencils, keeping the water inside?

When my 3-year old daughter (N) and I tried this out, we worked with the question, “what will happen if we poke pencils into a bag full of water?” That seemed more age-appropriate and tangible for her.

Magical Plastic Bag Experiment | TinkerLab


  • Zip-up Bag
  • Water
  • Sharpened Pencils

We filled a zip-up bag about half-way with water and sealed it up. I held the bag high over a sink and N poked the pencils straight through the bag, from one side to the other. This is where my fancy photography skills come into play, holding the bag with one hand and snapping a photo with the other. Are you impressed?

Make sure that the pencil doesn’t keep traveling through the bag or you’ll have water leaks.Magical Plastic Bag Experiment | TinkerLab

Magical Plastic Bag Experiment | TinkerLab

Keep adding pencils until you’ve had enough. Before removing the pencils, take a moment to talk about what you see. When the pencil goes into the bag, the bag seems to magically seal itself around the pencil.

Magical Plastic Bag Experiment | TinkerLab

When you’re done, remove the pencils over a sink.

The Science Behind the Experiment

Plastic bags are made out of polymers, chains of molecules that are flexible and give the bag its stretchiness. When the sharp pencil pokes through the bag, the stretchy plastic hugs around the pencil, creating a watertight seal around the pencil…and the bag doesn’t leak.

Magical Plastic Bag Experiment | TinkerLab

More Polymer Fun

Now I’m really excited for us to try poking skewers through balloons without popping them (QuestaCon Science Squad) and make our own kazoos from toilet paper rolls and plastic bags (Kazoologist). Steve Spangler Science is also an amazing place to go for projects like this, and you’ll find endless polymer-related ideas over there.

You could also make your own polymer by mixing up a batch of fun and flubbery Gak (a mixture of water, white glue, and borax). We’ve done this multiple times, and my kids can’t get enough of it.

More Science Projects for Kids

If you enjoyed this project, you’ll love this article: Science Fair Project Ideas.

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In case you blinked and missed it, Tinkerlab rounds up all the great stuff on the internets on keeping you and your critters creative and wraps it up for you in a tidy newsletter! (And throws in some secret giveaways for good measure!)  – Yuliya P., San Francisco, CA

Join our community and you’ll learn:

  • How to simplify your life and make more room for creativity
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10 Ways to Raise Creative Kids

“The creative is the place where no one else has ever been. You have to leave the city of your comfort and go into the wilderness of your intuition. What you’ll discover will be wonderful. What you’ll discover is yourself.” — Alan Alda

A version of this post was originally shared at Kiwi Crate.


Are you interested in raising your child to be their most creative self? The path to creative thinking isn’t a direct on, but there are a few landmarks that can help us find our way.


Here are 10 ways to raise creative children:


1. Make Mistakes

Stanford researcher and author of Mindset: The New Psychology of Success, Carol Dweck, shares that children who are afraid of failure are less likely to think creatively. If your child acts disappointed at making a mistake, try saying something like, “what can we do to change this outcome?” or “how could you do this again?” I like how my friend and colleague Ben Grossman-Kahn of The Nordstrom Innovation Lab calls this Failing Forward, or looking at mistakes as opportunities for growth rather than failures.

2. Get Messy

Most of us like a clean space and feel overwhelmed when messes get out-of-hand. However, when children are in their creative element, messes can quickly develop. The next time your child asks to paint or wants to dump a bag of cotton balls all over the floor, make room for it (and/or take it outside). You might have to contend with a mess, but the creative benefits will surpass this temporary inconvenience.

3. Offer Praise for Effort

We’ve all heard a lot about how praise can hinder a child’s independent thinking. In Alfie Kohn’s book, Punished by Rewards: The Trouble with Gold Stars, Incentive Plans, A’s, Praise, and Other Bribes, he talks about how rewards succeed at motivating people to….earn more rewards. The problem with praise is that it can strip a child from searching for his own internal motivations. This isn’t to say that all praise is bad, but next time you’re tempted to praise, try saying something objective such as, “I see that you put your shoes on by yourself,” or “You’re working really hard on that math problem.”

4. Be open-minded

Offer your child choices as a way to encourage independent thinking. You may not be in the habit of eating dinner for breakfast, but if your child says she wants to eat pasta before heading off to school, make room for that. If she wants to help in the kitchen, try turning your kitchen into a science lab and give her open access to a handful of ingredients and kitchen tools.

5. Model Creativity

What’s your creative outlet? Where do you enjoy putting your creative energy? Cooking, singing, gardening, drawing, dancing? Children who watch their parents engage in creative activities are more likely to embrace these activities themselves. If it’s been a while since you’ve done something creative, think about what made you happy in your own childhood and spend half an hour doing that activity with your child. How did it feel? Could you try it again tomorrow? And the next day?

6. Step Back

This may seem to contradict #5 a bit, but it’s important to remember that this is all about striking a balance. If a child feels like she’s constantly under surveillance, she may be less likely to take risks, which would diminish her creativity. If you encourage autonomy, you’ll see your child’s imagination bloom. The next time your child is engaged in quiet play, drawing, or writing, refrain from jumping in with a comment like “what are you drawing?” This will only pull him out the zone. Instead, make yourself a cup of coffee and enjoy a moment to yourself!

7. Set aside creativity time

This can be hard, especially for working parents, but children need unstructured time to imagine, build, experiment, and explore. It could be half an hour after dinner, drawing time in bed before reading a book, or an hour of imaginative play every weekend. Look at your schedule and make sure that there’s time set aside for this.

8. Get Back to the Basics

Toys that beep and flash are fun, and definitely have their place, but they don’t build creative thinkers the way sticks, tubes, blocks, dolls, office supplies, sand, and water do. Spend some time watching your child play and take a quick inventory of your toys. What do they play with the most? What objects do they pull into imaginative play? Can you swap a close-ended toy (for example, a toy with buttons that has one or two functions) with an open-ended toy (like blocks that encourage free play)? This post by Amy Anderson for SimpleKids is full of great ideas: Creative Pretend Play Props and Ideas

9. Minimize Screen Time

It can be hard for some families to remove screen time altogether, but we can all make an effort to spend less time in front of the screen. Time spent watching videos or cartoons could be spent drawing, building a city out of blocks, or serving up play dough cupcakes. What could you do to reduce screen time?

10. What other ideas do you have for raising creative kids?

There are so many ways to encourage a child’s creativity, and I’d love to hear what works for YOU! What would you add as the #10 way to raise creative kids?


Microwave Marshmallow Experiment

Have you heard of the microwave marshmallow experiment? It’s really simple and a fun way to explore how the volume of gas expands a marshmallow as it heats up. My kids also enjoy this experiment because it mixes science (+ fun) with a sugary treat.

The fun and simple microwave marshmallow experiment | Tinkerlab

Microwave Marshmallow Experiment Supplies

  • 4 (or more) Marshmallows
  • Paper Towel or Microwave-safe plate
  • Microwave
  • Paper to jot down observations (I’ll share my 3-year old’s observations in italics below)
For this microwave marshmallow experiment, we’ll microwave three marshmallows for different periods of time, and then  compare what happens to the marshmallows as they heat up, and then cool down again. This is an engaging way to involve children in scientific observation and discovery, it raises lots of questions, and doesn’t require a lot of prep or clean-up. Are you with me?

Step One

Microwave one marshmallow for 10 seconds and remove from the microwave. Compare it to an uncooked marshmallow and describe how it looks. How does it feel?

The fun and simple microwave marshmallow experiment | TinkerlabObservation: It’s small, shorter than the other marshmallow, but fatter. It’s gooey.

The fun and simple microwave marshmallow experiment | Tinkerlab

Step Two

Microwave the second marshmallow for 30 seconds and remove it. How does it compare with an uncooked marshmallow? What happens to it as it cools?

Observation: It’s a little bit larger than the other one. It got dry as it cooled.

The fun and simple microwave marshmallow experiment | Tinkerlab

Touching the second marshmallow.

The fun and simple microwave marshmallow experiment | Tinkerlab

Cool, a little hole showed up in the middle after it cooled down a bit.

The fun and simple microwave marshmallow experiment | Tinkerlab

Step Three

Microwave the third marshmallow for 50 seconds and remove from the microwave. Compare to and uncooked marshmallow right away and after it cools. How are they different? How does this marshmallow feel?

Observation: It’s huge and wrinkly and dry. It’s brown. That means it burned. That means it’s good to eat. Crunchy to eat.

The fun and simple microwave marshmallow experiment | TinkerlabYou can see all three marshmallows here. We noticed that the 30 second and 50 second marshmallows got hard and crunchy as they cooled, and N decided to taste them for a flavor comparison.

The fun and simple microwave marshmallow experiment | TinkerlabThe 50 second marshmallow was brown, crunchy, and caramelized. Have you ever tried astronaut ice cream? It had a similar texture.

The science behind the activity is explained clearly over here at The Exploratorium. In essence, the volume of gas in the marshmallow increases when the temperature increases, and then decreases as it cools down. The Exploratorium suggests not microwaving marshmallows for longer than 2 minutes, less you want a dark, stinky, burnt mess on your hands.

This project was inspired by a book we found at the library: Kitchen Science Experiments: How Does Your Mold Garden Grow?

Have you ever microwaved anything and been surprised by the outcome?


Science for kids microwave marshmallow experiment copy

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In case you blinked and missed it, TinkerLab rounds up all the great stuff on the internets on keeping you and your critters creative and wraps it up for you in a tidy newsletter! (And throws in some secret giveaways for good measure!)  – Yuliya P., San Francisco, CA

Join our community and you’ll learn:

  • How to simplify your life and make more room for creativity
  • How to make hands-on making a part of your everyday life
  • Easy, actionable ways to raise creative kids

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