invisible ink experiments, invisible ink recipe, invisible ink for kids

Spy Kit: Mission 7, Part 1 

Spy Kit for Kids

CALLING ALL AGENTS: It’s time to create a spy’s most valuable writing source…disappearing ink! Create this simple yet resourceful tool to write to your friends' secret messages without others seeing 👀 … We’re breaking Mission 7 into 2 parts - Invisible Ink and Invisible Ink Revealer. Grab your Spy Kit and let’s begin! 


How Long Does Invisible Ink Last?

The ink will fade in the sunlight in about a week. If you don’t want your nemesis spies to see your secret note, leave it out in the sun to disappear forever!  If you want to keep your note longer, keep it out of sunlight and use non-glossy paper. 


How to Make Invisible Ink: 

1. You’ll need the following materials to make the invisible ink: water, baking soda, a yellow measuring spoon, and a test tube. All of this can be found in your spy kit!

Materials needed to make invisible ink


2. Place 3 large, yellow spoonfuls of baking soda (bicarbonate of soda) into a test tube. I kept the test tube in a plastic cup to keep it upright.

Scoop three spoonfuls of baking soda into test tube


3. Add water to the test tube with ½ inch of space left from the top. Need a little air bubble to better mix the solution.

Pour water into test tube with 1/2 inch space at top 

4. Screw the cap on tightly and shake the tube to mix the baking soda with the water. It will want to separate as soon as it mixes - so remember to shake it up in between each use. 

Screw the lid on the test tube and shake to mix the solution

5. After giving it a proper shake, carefully unscrew the cap and pour a little into the small cylindrical container. This will make a nice ink well and our invisible ink it ready to be used! 

Pour ink into small ink well

6. Dip the end of your quill into the ink and practice writing with page 3 in your Mission 7 envelope. Try “Be a Voice, Not an Echo” a famous quote by the great scientist Albert Einstein! 

Dip quill into the ink and practice writing with invisible ink

7. Once you get the hang of it, write a message on a separate piece of paper. TIP: Try writing letters larger than you usually write until you get the hang of it! Let your message completely dry before using the Invisible Ink Revealer - stay tuned on how to make that in the next blog! 

Write your own message on a separate piece of paper

Take a look at this video to see how to make the invisible ink from start to finish! 


What is the best Spy Kit?

Spy Kit form Learn & Climb! Solve puzzles, test out science experiments, make spy gadgets, and more?! There are 55 TOTAL activities to ignite critical thinking skills! link to spy kit

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