oshc activities
Spy School / Invisible Ink Letters

Invisible Ink Letters

Older children write secret messages in lemon juice, then an educator reveals them with gentle heat.

How to run it

  1. Squeeze lemon juice into small cups.
  2. Write a message on paper with a cotton bud dipped in juice.
  3. Let the paper dry.
  4. An educator holds the paper near a warm lamp or uses an iron to reveal the writing.

You will need

  • lemon juice
  • cotton buds
  • paper
  • cups
  • iron or warm lamp (educator only)
Make it easier or harderYounger children draw a picture, while older children write coded messages.
SafetyOnly educators handle the heat source, and keep lemon juice away from eyes.
My Time Our Place · Outcome 4, Outcome 5Children use writing and explore a chemical change.

Fits these theme days

Spy SchoolDetective DayScience WeekEscape Room Day

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