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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Make Your Own Egg Tempera Paint

Today I’m sharing how to make homemade tempera paint. This paint is beyond simple, made from eggs and food coloring, and it will last indefinitely once dry.

How to make homemade tempera paint with just eggs and food coloring.

I’ve been interested in whipping up a batch of homemade egg tempera paint for a while, and was eager to try this with my kids.

History of Egg Tempera Paint

Do you know the history of egg tempera paint? It’s quite interesting, actually.

Egg tempera was wildly popular amongst Early Renaissance artists (Botticelli, Giotto, Fra Angelico) and then fell out of use with the Late Renaissance artists (Leonard da Vinci, Michelangelo) when oil paint was introduced. To make egg tempera paint, powdered pigments culled from things such as stones, sticks, bones, and the earth were mixed with water and then tempered with a binding agent such as an egg. And when they were tempered with eggs, they were called egg tempered paints and eventually earned the nickname Egg Tempera.

Interesting, right? So this is where those big, bright bottles of kid-friendly tempera paint get their name from.

I borrowed this recipe from Kid’n’Kaboodle, and if you click over there you’ll find an enormous list of recipes that will keep your little artists busy for a long time.

This project doesn’t take very long to set up, kids will enjoy making their own paint from eggs (unless they’re allergic or hate eggs, of course), and once the paint dries it has a gorgeous, shimmery patina that makes it painting-worthy.

make egg tempera paint with kids

Ingredients: Tempera Paint

This post includes affiliate links

  • Eggs
  • Small bowls
  • Paint Brushes
  • Liquid Watercolors or Food Coloring
  • Card stock or other heavy-weight paper
  • Sharpie Pens – this set is a GREAT deal, by the way

How to Make Tempera Paint

make egg tempera paint with kids

Separate the yolks from the whites, and drop one yolk into each of your bowls.

make egg tempera paint with kids

My 3.5 year old chose three colors to add: Purple, Sparkly Red, and Sparkly Blue. We like the Sax Liquid Watercolors. The bottles are inexpensive, last forever, and come in a huge range of colors.

As soon as my one year old began mixing the purple into the egg yolk, my older daughter commented on how purple and orange mix together to make brown. Not her desire, exactly, but she didn’t seem to mind and it was a great little unintended lesson in color mixing.

kids paint with homemade egg tempera paint

Make Some Paintings

With our homemade tempera paint ready, we got busy painting. Quite a lot of painting, actually. For this step, I used paper from a big ream of white card stock purchased from the office supply store.

drawing with sharpie

I joined in too and it occurred to me that this transparent paint would make a beautiful luminous sheen over some bold Sharpie marks. I offered my kids Sharpies, and they thought it was a great idea too.

Do your kids love Sharpies as much as mine do? My kids go bananas over Sharpies and I sometimes wonder if it’s because they really are all that wonderful or if it’s because I keep them on a super-high shelf, buried behind old taxes and holiday Silverware.

child paints with homemade egg tempera paint

This was a great move, and the effect was as pretty as I had imagined.

toddler paints with homemade egg tempera paint

My toddler isn’t so deft with the Sharpie and I had to keep a sharp eye on her. She also insisted on the famous paint-draw technique, which kept me busy. How I even snapped this photo I’m not sure.

kids paint with homemade egg tempera paint

Before we wrapped it up, they wanted to collaborate with my on my drawing. Rainbow asked me to draw her a sheep, and then the two of them went to town painting in and around the scene.

More Homemade Paints

We have this awesome collection of homemade paint recipes that includes:

  • Puffy Sparkle Paint
  • Finger Paint
  • Sweetened Condensed Milk Paint
  • Invisible Ink
  • and more!

St. Paddy’s Day Photo Booth

st paddys day photo boothI’ve  always loved St. Paddy’s day, and then I lucked out and married a cute Irishman. We spent part of our honeymoon in Ireland, and the green island holds a special place in my heart.

A few weeks ago I asked the Tinkerlab Facebook community for some ideas on what I could do with a huge pile of old sheets. I got tons of great ideas, and we started by making a Simple Clip Fort. I’m working my way through the list, and today we’re making a photo booth backdrop for St. Patty’s Day.

Before going to bed I hung a white sheet over one of our curtain rods and secured it with two big clips.

cut out shamrocks for photo boothI cut a handful of shamrocks from green paper and placed them on a table with double-stick tape. Altogether, the prep took me about 10 minutes. When my kids woke up, they were excited about the invitation, got dressed in greenish clothes, and we got right to work.

tape shamrocks for photo boothI helped 3-year old N stick some tape to the back of the shamrocks. Double-stick tape is tricky stuff for little hands! Then she and my 1-year old stuck them to the sheet. Well, my 1-year old mostly tore the shamrocks in half and we had to find a more constructive activity to distract her for a few minutes.

I moved a green rug over to the curtain area and that’s when the dance party started. I snapped a couple archive-worthy photos for the family photo album, and then it was mostly just playing in fron to the clover curtain.

st pattys photo boothOn St.Patty’s Day itself, we serve up green milk in mugs, delivered with a bit of magic. We add a couple drops of green food coloring in the bottom of a dark mug, the kids say “Sean Beggorrah,” and then we pour white milk into the mug for a leprechaun-delivered surprise. This tradition comes down through my husband’s family and I haven’t met anyone else who does this. Is this part of your St. Patrick’s Day traditions?

We’ve been talking about building a leprechaun trap, but I’ve never built one before. Have you? Do you have any tips? And I’m always thinking about fun ways to add magic to this holiday and would love to hear how you celebrate St. Paddy’s Day with your kids.

More St. Patrick’s Day fun from the Archives

Rainbow Play Dough

Spring Sink Mat Print

Fairy Doors 

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?

Sensory Activity: Shredded Paper

If you’re afraid of a mess, I have to warn you up front that this is a messy one.

But it’s not a dirty kind of mess and if you stick with me here, you might become a shredded paper convert like me.

paying bills with kidsIt all started innocently, and rather boring, enough. It was a bill-paying day, and I set the kids up with their own stack of mailing labels stickers, pens, and old checkbooks while I dealt with the heavy stuff.

They were happy enough, but things heated up when we moved on to paper shredding

shredding paper in paper shredder with kids

I had basket full of old bills that were ready for the shredder, and two happy-to-please assistants who took the shredding job very seriously.

Shredders are potentially dangerous, and I would absolutely not let my kids shred on their own, but with careful supervision the act of shredding can build confidence, teaches accuracy and careful attention to details, and it’s just plain fun to make a loud ruckus.

When it’s not in use, I unplug the machine and lock it in a closet. When it’s in use, I run through the rules of good shredder usage with my three and a half year old: Up to 3 sheets at a time. Hold the paper at the top when you feed it in (no fingers near the shredding area). And it’s not for my 18 month old.

While my three year old shreds, her sister hands her stacks of paper. They love it.

Okay, so take a look at that little basket of paper up there and remember how small it appears. And remember that appearances can be deceiving.

My friend and her son came over a couple hours later to play and make some ice cream. While we were talking, my 18 month old dug her hands deep into the neatly packed shredded paper bag, and in moments the room erupted into this happy play scene…

play in shredded paper with kids

And that’s only half of the paper.

They could not have been happier. In fact, just before this moment, the kids were all winding down and ready to go their separate ways. But as soon as that bag emptied out, they found a whole other hour of play inside their little souls.

It was so fun, in fact, that my older daughter chose to keep playing rather than go to her beloved gymnastics class.

play in shredded paper with kidsMy friend is a master at imaginative play with kids, and had them bury themselves in shredded paper, pretend they were dormant volcano monsters, and then erupt without any notice. You can probably imagine the shrieking and laughter that followed.

And we all agreed that this is the perfect toy: free, open-ended, and entertaining for a long spell.

So it was messy, yes, but it was easy enough to sweep up. And rather than cart it off to the recycling bin like I had planned, it all found its way back into the closet and ready for another day of fun.

More Shredded Paper Ideas

Alpha Mom makes a bird’s nest with brown paper bags.

10+ Ideas on what you can do with Shredded Paper (like make animal bedding, papier mache, and mulch) from Bohemian Revolution.

Adorable and seasonal Shredded Paper Seed Starters from Made. These are on my to-do list.

Can you think of a time that your kid/s turned a banal situation into a burst of play? Have you played with shredded paper? Would you try this yourself?