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?

Explore Modern Artists: Painting with Edward Hopper

Welcome to the first project in our newest series: Explore Modern Artists. Today we’ll take a look at one of my favorite American Artists, Edward Hopper, with a preschool-friendly painting technique.

Explore Modern Artists with Kids : series of projects on Tinkerlab

The Q-tip painting technique that we used could be applied to the work of just about any 2-D artist, so definitely take this as inspiration and run with it in another direction if that works better for you. If you’d like to connect the technique with the artist, take a look at the work of Georges Seurat, who painted with dots of paint.


Explore Modern Artists: Edward Hopper

I thought we would begin with Edward Hopper because it’s been warm and sunny around here and my kids and I have been looking at some of his paintings as we talk about an upcoming visit to Cape Cod, which is where Hopper had a home and studio. Edward Hopper’s iconic seashore paintings masterfully capture light and evoke a sense of calm, while transporting us to the Eastern Seaboard.

My children are preschoolers and I wanted to make this a project that would be fun for them while encouraging them to look closely at Hopper’s work. This technique has little to do with Hopper’s work, but it got my kids talking about what they saw in his pictures while inventing their own patterns of color.

set up edward hopper art project


edward hopper kids art


The project itself is easy to set up and children will enjoy learning about an artist while layering paint on top of his images. Give yourself 20+ minutes for set-up, the activity, and then clean-up.

When we paint, I cover our table with a plastic tablecloth. Each child had a paint palette filled with dollops of tempera paint, and a big cup of Q-tips, which we used as brushes. You could use brushes instead, but they thought the Q-tips were fun.

We selected a few paintings that we enjoyed. I’m adding links to the images in case you’d like to use these too.

Before the painting began, 4-year old N and I talked a little bit about Edward Hopper while looking at some of his art. I gave her an age-appropriate synopsis of his life and then we talked about what we saw happening in his paintings. This bit was under 5-minutes because she was excited to paint. Fair enough.

ground swell edward hopper inspired

More on Art Looking

I’m a huge fan of an in-school program called Visual Thinking Strategies (VTS), which helps children build visual literacy and critical thinking skills through the process of looking closely at a work of art. A facilitator sits in front of a group of children and leads an interactive discussion about one work of art. I’ve led many of these discussions myself, and the energy around these conversations is palpable. To see VTS in action, there a some great videos on the Visual Thinking Strategies website. 

More from Explore Modern Artists

Paint like Jasper Johns

Watercolors in the Bath

How does bath time go in your home? My 4 year old prefers the morning shower to a bath and my 22-month old, who’s mostly loved her baths, recently started giving us a hard time about bathing.

Over the last few years my husband and I have come up with all sorts of creative solutions to encouraging our kids to bathe. I wonder if you’ve tried any of these tricks?

    • Offer your kids water-resistant dolls with soap and washcloths for “Baby bath time”
    • Fill a bath-side bag with toys (rubber ducks, buckets, cups with holes in them, etc.)
    • Bubble bath
    • Craft foam in the Tub
    • Bubbles (for blowing) with bubble wands
    • Bathe in the dark with flashlights,/candles/glowsticks
    • Bathtub Crayons

This bath time invitation is just a simple Washable Watercolor set.

All you need is a watercolor box and a paintbrush. The box usually come with a brush, so this takes about two seconds to pull together.

watercolors kids bath

Little Rainbow dipped her brush in all the colors, individually and then mixed together. This is a new one for me, and it was so popular with my Rainbow that 4-year old Nutmeg asked if she could jump in too. She usually prefers to shower alone, so I thought this was the best kind of endorsement.

watercolors kids bath

Rainbow painted while her big sister washed the paintings away.

When they was done, the paint box was a mixed up mess, but I just rinsed it out and the colors sprang back to life.

The only trouble I had was with cleaning the paint. All of the colors washed away, except for the black. It came right off the tiles, but left a grey shadow on my white tub. It washed right away with a little bit of Bar Keepers Friend, my favorite porcelain cleaner. But the fun that was had (and the clean bodies that went along with that) was well worth a little elbow grease for me.

More Creative Bathtime Fun

Two of my favorite spots to visit for creative bath play are Growing a Jeweled Rose and The Imagination Tree

  • Crystal at the fun kid-friendly blog, Growing a Jeweled Rose, is the Queen of bath play. She has a whole category named Sensory Baths, that will keep your little ones wet and happy.
  • One of my favorite bath activities from Crystal is her glow-in-the-dark outer space bath. OMG — it’s ridiculously cool.
  • Crystal has an entire Pin Board called Play in the Bath
  • Anna at The Imagination Tree shows us how to make Shaving Cream Bath Paint. Her photos make the paint look like frosting.
  • Also inspiring are Anna’s Multi-sensory bath time photos, where she colors the bath water (and reminds us that the color will not stain our kids’ skin).

Do you have tricks for making bath time more fun (and/or luring your kids into the bath)?


10+ Messy Art Projects That Will Leave Your House Clean

messy art projects that leave your house clean

I can’t tell you how many emails, comments, and messages I receive with questions about how to set up no-mess art projects. A really good friend of mine recently told me that she loves my blog, but that my projects are so….MESSY. Eeek.

I’m not sure if you’ll believe this but the funny thing is that I’m afraid of messes too. Messes themselves don’t really bother me, but it’s the prospect of cleaning messes that often gets the better of me. I already have dishes to wash, clothes to clean and fold, and floors to sweep, so adding one more mess (that doesn’t really have to be made) is a hard thing to voluntarily add to my to-do list.

So I thought you might also enjoy a few tips for setting up “messy” art projects that will leave your house clean. Oh, and just in case you decide to shut that out mess-filter and your kids go a little nutty with crayons + walls, I’ll also include some ideas for cleaning that mess at the end of this post. Just in case.

Trays Teach Preschool

Place large serving trays or cookie sheets beneath small pieces of collage paper for easy clean-up. Read Using Trays in the Preschool Classroom for more clever early childhood education ideas from Deborah at Teach Preschool.

muffin tin mom starbucks cup paint

Fill Dome-lidded Starbucks cups with paint. The brush goes right into the straw holder. A brilliant solution to the otherwise spillable paint cups from Muffin Tin Mom.

mama smiles plastic bag

Mess-free painting in a bag couldn’t be cleaner, from Mama Smiles.

momtastic sponges

Add some paper and sponges to paint and ziplock baggies for more clean painting. From Steph for Momtastic. Steph is also the owner of one of my favorite blogs, named appropriately for this post, Modern Parents Messy Kids. 

Sharpie Tie Dye Shirts

Sharpie Tie Dye Shirts look like they’d make a mess, but it’s all done with Sharpies and rubbing alcohol. My daughter loved this when she turned 3. From Mom’s Crafty Space.

Contact paper and tissue paper are a classic combination for this easy and clean suncatcher that kids will have fun making (Tinkerlab). The Artful Parent is the Queen of suncatchers, and lucky for us she just assembled all of her Suncatcher posts into this post: Suncatchers and Stained Glass, 39 Ideas for Kids

the mad house tape

Tape off your drawing paper will keep the edges near the table clean, and will also create a nice, crisp border around the picture. I also cover our tables with a plastic tablecloth or butcher paper when using messy materials. From The Mad House.

paint in oatmeal container

Find out what Deborah from Teach Preschool placed in the Oatmeal container to make unique, active, and clean paintings.

clean-er finger painting baballa

Add paint to sponges for clean-er finger painting. From the Spanish-speaking blog Barballa — if you don’t speak Spanish, still check it out — the photos are beautiful and tell the whole story.

spaghetti worm painting chocolate muffin

Place painting projects inside a box, as Melissa at The Chocolate Muffin Tree did here. Read more about how they made these creative Spaghetti Worm Paintings.  You can also read how we made Rolled Easter Egg paintings (seen in the first photo of this post) here. 

Save larger cardboard boxes to create cardboard box splat paintings. This is good one for outside…just in case! (Tinkerlab)

One of my all-time favorite blogs, The Artful Parent, shows this simple way to paint with just water and a chalkboard. Check out Jean’s blog for more ideas. She’s a keeper.

magnetic tote family fun

Family Fun has this clever solution to storing art supplies — neatly — on a table, using magnets and a muffin tin.

Remove Crayon Stains Around the House

And when your heart skips a beat at that too-late moment when the house gets really quiet, DIY Life shares a gazillion cleaning suggestions for when your little cutie pies go to town with crayon on the eggshell painted walls, carpets, clothes, and flat-screen TV’s.

Do you have any tips for messy art projects that will leave the house clean?

How to Make Paint: Sweetened Condensed Milk

sweetened condensed milk paint diy from tinkerlab

This recipe is a keeper because it comes together quickly, uses ingredients you probably have on hand, and it expands the way children think about art supplies. When children have the opportunity to invent things and imagine new possibilities (in this case, making their own paint, inventing colors, and imagining what they can create with the paint), opportunities for creative thinking are greater.

Not to mention, both of my kids (21 month Rainbow and 4 year old Nutmeg) enjoyed painting with it, and, um, eating it too. Once dry, the paint has an attractive shiny coat to it. Because there’s sugar in the milk, I’m not going to guarantee its archival quality, but after we’ve had our paintings for a month they still look brand-new.

I get a lot of questions about activities that can be enjoyed by kids of multiple ages. Generally, my opinion on this is that children will adapt the materials in front of them to meet their own level of ability. This project will work for toddlers on up to adults; just expect that the results will vary.

how to make sweetened condensed milk paint

My 4-year old’s completed paintings.

how to make sweetened condensed milk paint


  • Sweetened Condensed Milk
  • Food coloring
  • Small mixing bowls
  • Paint brushes
  • Tea spoons for mixing
  • Card stock or other heavy paper for painting on

how to make sweetened condensed milk paint

Pour a little milk into a bowl, add a couple drops of food coloring, and mix.

how to make sweetened condensed milk paint

My 21-month old got into the mixing action too.

how to make sweetened condensed milk paint

Our painting set-up: I have a big, clear plastic tablecloth that covers the art table. It’s perfect for sticky + wet projects like this. I taped my toddler’s paper to the table to keep it from slipping.

how to make sweetened condensed milk paint

These paintings takes some time to dry. Rainbow did not have a delicate painting hand and her paint went on quite thick. The painting on the right had a deep puddle on it that took a good day to dry. And when it finally dried it caked up a bit and had a nice crackled effect to it. Just something to keep in mind in case you’re looking for a quick-drying paint…this is not it!

Have you tried this before? What kitchen supplies have you tried painting with?

And be truthful, aren’t you just a little bit curious about what it would be like to paint with sticky milk?

This post has been shared on It’s Playtime