Invisible Ink: Easy Summer Science Activity

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With the arrival of summer, you are probably on the lookout for easy, engaging and entertaining activities to keep your little one occupied and stimulated. Look no further! Today, we’re going to explore a classic science experiment that combines curiosity, creativity, and a touch of magic to create secret messages with invisible ink made with lemon juice. This exciting activity is sure to captivate young minds and provide endless hours of summertime fun.

WILL YOU TRY MAKING INVISIBLE INK WITH YOUR LITTLE ONE THIS SUMMER? Pin it for later!

How to Make Invisible Ink

Squeeze lemon juice from a lemon into a small bowl. Don’t worry if the seeds pop in!
Take a q-tip and use it to draw a picture or write a message on a piece of white paper. The more lemon juice the dark the message will appear.
Set the paper aside to dry for at least 15-20 minutes depending on how much juice you used.
Time to reveal your message or your picture using a safe heat source. Adult participation is required for this part. You can either use a light bulb, and iron turned to medium and ironing board or oven mitts and your stove turned to medium. It will take 10 to 30 seconds to uncover your message!
Let your paper cool down before touching it.

What else to try

Compare other citrus fruits like oranges or grapefruits, or even onion juice.
Try diluting the lemon juice with a small amount of water to make the ink even more invisible on the paper!

What’s happening

Lemon juice is acidic but also has sugars in it. When you write on the paper the acid reacts with the paper fibers to make more sugars. Then when you heat up those sugars, they release carbon which oxidizes when it comes in contact with the oxygen in the air and turns brown.

Looking for more summer activity ideas? Check out of these other round-ups for more ways to stay busy this summer:

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Toddler and Preschooler Curriculums, Books & TV Show!

Play2Learn Toddler & Preschool Programs for Curious Toddlers

There is no limit to your toddler’s energy and curiosity. That energy and curiosity although a joy can be challenging at times. Their interest in just about everything around them is what makes them great learners. One and two year olds can soak up so much just from their senses!

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Book: Exciting Sensory Bins for Curious Kids

Did you know I wrote a book of sensory bins? Click here for more information Exciting Sensory Bin for Curious Kids. Or grab your copy at Amazon.

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TV Show: Curious Crafting

I’m so excited to share my crafting TV show Curious Crafting which launched in July 2022 on TVOkids and TVOkids YouTube! Season 2 airs in the summer of 2023! We were also nominated in 2023 for Best Live Action Preschool Series by the Youth Media Alliance Awards of Excellence.

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