Invisible Ink

Transform into a secret agent with the power of science! Using lemon juice as invisible ink, you’ll create hidden drawings and messages that can only be revealed by the warmth of a light bulb. This activity not only nurtures creativity, but also introduces basic scientific concepts in a fun and engaging way.
Invisible Ink - Kids activities

Summary

Appropriate kid’s energy level

Tired

Skill(s) developed

Creativity, Fine motor, Problem-solving

Prep time

10 minutes

Type of activity

Arts/Crafts, Science

Appropriate setting(s)

Indoors

Material(s) needed

Lemon juice, Paper, Paintbrush or cotton swab, Light bulb

Easy mode

Start simple by using your invisible ink (lemon juice) to draw basic shapes or write letters on a piece of paper. Use a paintbrush or a cotton swab for more control. Once your drawing is dry, hold it near a light bulb and watch as your invisible creation magically appears!

Hard mode

Level up your secret agent skills by writing secret messages with your invisible ink. Parents or friends will love decoding your mysterious messages. Remember, the message will only reveal itself when held near a light bulb.

Challenge mode

Ready for an epic adventure? Create a treasure map using your invisible ink. Draw paths, landmarks, and an X to mark the spot where the “treasure” is hidden. Once the map is dry, let someone else hold it near a light bulb to reveal the path to the hidden treasure. Let the treasure hunt begin!

Some prompts to encourage the kid

  • Wow! You’re like a real secret agent with your invisible messages!
  • Can you draw a secret picture for me to guess?
  • Let’s see if I can decode your hidden message!
  • Do you think the treasure is far? Let’s follow your invisible map!

Important things to keep in mind

  • Ensure children are supervised when holding the paper near a light bulb
  • The bulb can get hot and may pose a burn risk.

More ideas to support your Screen-Free journey

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We’re parents, just like you – trying to raise curious, creative kids in a world full of screens. Screen Free Kids started as a personal project to rediscover simple, joyful ways to play, learn, and connect. Now, we share those ideas with thousands of families  – through thoughtful activities, parenting guides, and a book full of inspiration. More about us.

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