Secret Lemon Gift

Sau Fen Chee · 70 ·

Have you been keeping a diary? Or penning a book about how you are spending all your time at home away from school? Or working on a secret mission with your friends from VIVITA or from school? If you want to keep your secrets from prying eyes until they are ready to be read by your best friend or send a surprise message to cheer someone up, Joylynn, who recently joined the VIVITA crew as an intern, has a great idea for you to try out!

How did you come up with the idea for your project?

The idea comes from wanting to encourage kids to use their creativity to make original gifts. During this period, warm touches like these also contribute to bringing joy to people around us.

What makes this a cool project?

One lemon makes two mini projects!

Could you share with us a bit about your prototyping process? What did you learn from the more memorable failed attempts?

It was a fun and meaningful process! There were some materials that I did not have, so being able to source for alternative tools during the process gave me the confidence that this project could be suitable for most households too! Many tools can be reused for both mini projects and I hope that this could show kids the power of being resourceful and sustainable!

For the secret message to be revealed, I was told to place it over a warm bulb which unfortunately did not work… More heat is needed. So, I tried using flames or hair dryer, both of which work! Understanding the science behind the lemon secret message helped me to discover alternative solutions.

(Science behind secret message… Heat causes some of the chemical bonds to break down, freeing the carbon, thus revealing the secret message! It’s important to understand the science behind how things work.)

What materials do you need?

  1. Lemons
  2. A piece of old cloth
  3. Paper
  4. A few drops of water
  5. Paint (Acrylic preferably)

What tools do you need?

  1. Cotton swabs / paint brushes
  2. Ice-cream stick / fork
  3. Paper towel / paper plates / paint palette
  4. Old newspapers for less cleaning work!
  5. Hair dryer / heat source


Secret Message

Do lay out newspapers on your work table for easier cleaning up.

Step 1: Take half a lemon and use a fork/ ice cream stick to extract the lemon juice, keep the lemon for the next activity

Step 2: Pour a teaspoon or few drops of water in

Step 3: Mix it thoroughly

Step 4: Use a cotton swab/ paint brush to dip into your special formula and write the secret message

Step 5: Leave to dry (while drying you can move on to the Lemon Stamping)

To reveal the secret message, use an iron or hair dryer over the paper.

Lemon Stamping

Do lay out newspapers on your work table for easier cleaning up.

Step 1: Take both the squeezed and fresh(un-squeezed) halves of lemon from previous project and choose your favorite paint color.

Step 2: Use a cotton swab/ paint brush to spread the paint on the surface of the lemon.

Step 3: Lay out your cloth and start stamping! Switch between both fresh and squeezed lemons to see different stamping effects!

Step 4: Leave to dry


Lemon juice is a weak _____. (Could you fill in the blank?)

Combine it with water to create the invisible ink! When exposed to heat this causes carbon to break down revealing the secret message!

What else can you use to create invisible ink?

Make a special gift with a secret message


Try different fruits and vegetables for stamping!