Invisible Ink

We found this fun book called The Ultimate Book of Kid Concoctions by John & Danita Thomas at the library.  This activity, called Magic Paint, is what we decided to try out first.


  • 1 Tablespoon baking soda
  • Water
  • 4-6 drops of food coloring
  • Paintbrush
  • Paper
  • Hair dryer (optional)


First mix 1 tablespoon of baking soda and 2 tablespoons of water together.

Next take your paint brush and start writing a secret message or draw a picture with the baking soda/water mix.

When finished, you’ll have to wait until the message is completely dry before continuing to the next step.


We decided to speed up this step by using a hair dryer.


All dry!


Next get 1 Tablespoon of water and mix it with 4-6 drops of food coloring.
To reveal your secret message, paint the food coloring water mixture over your message.

He was so amazed!  Next time we do this activity my son said he wants to use multiple colors when revealing his message/drawing. This would be a fun activity for older kids to write secret messages to each other….or even at a pirate themed party with invisible treasure maps to decode.

I don’t know if you can tell what he drew…it’s a train (Thomas of course..which is why he drew the #1) riding on train tracks, with a sun in the sky.