Give it a Try, it’s DIY! Let’s Make Invisible Ink


  1. How to make your very own invisible ink
  2. The history of invisible ink
  3. How to make learning history fun


If your child is a history fan or is intrigued by how things were done way back when they will love this super-cool DIY video. Not only will they learn how to write private messages, but they’ll also find out how to read them too! The secret ingredient? Lemon juice! 🍋


How to make your very own invisible ink


Not only is this fun DIY activity great for your little history buff, but budding arts and crafters will enjoy this too! After you’ve watched the video, keep reading to find out some interesting facts that you can share with young, inquiring minds about how invisible ink has been used throughout history. 📜

For your invisible ink, you’ll need:

  • Lemon juice
  • A paintbrush or a cotton earbud
  • A piece of paper
  • A small cup
  • A heat source: either a light bulb or flame ⚠️ Please be careful when standing near a naked flame ⚠️

OK, let’s go!

  1. Squeeze or pour a tablespoon of lemon juice into the cup.
  2.  Take a cotton earbud or paintbrush and dip into the lemon juice, swirling off any excess so that it’s not too wet.
  3.  Draw your picture, message or symbol onto the small piece of paper using the cotton earbud or paintbrush and wait for the paper to dry completely.
  4.  Hold the paper over a lightbulb, lighter or stovetop and voila – your message will be revealed! 👀


The history of invisible ink


  • Around 18 BCE, a Roman poet called Ovid included a section in his book, Ars Amatoria (Art of Love), that encouraged women to try secret writing to communicate with lovers that weren’t their husbands. He instructed that they should use fresh milk to write the messages, and for them to be read, powdered charcoal applied over the top was the key.
  • Later on, fruit juices joined the invisible ink party. Around 600 CE, Arabs used lemon juice to deliver secret messages between desert towns. Lemon juice, however, became most popular in the 16th century in Europe when monasteries used it to protect trade secrets. Juices were even used as late as World War II when prisoners of war used them to send hidden messages to people back home.
  • Eventually, the uses of invisible ink – also referred to as ‘sympathetic ink’ – went beyond secret-keeping and, with some much-needed updates to formulation, became a fixture in the world of aesthetics. Colour-changing inks were popular in 18th-century Parisian salons where they were used in decorative fireplace screens that, with a change in temperature, would transform from bleak winter landscapes to vibrant spring scenes, for example. 🌷
  • Unfortunately, not all attempts at using invisible ink went so well, and philosopher, Jean-Jacques Rousseau, discovered this the hard way. In 1736, he experimented with a dangerous combination of quicklime and orpiment (a rare mineral that contains arsenic sulfide – a highly-hazardous substance) and after mixing the two in a bottle, it exploded in his face causing him to swallow so much chalk and orpiment that he couldn’t see for more than six weeks! 😮
  • In 1965, a Navy pilot called James Stockdale was shot down over Vietnam and sent to Hanoi’s Hỏa Lò Prison, which was sarcastically nicknamed the "Hanoi Hilton". During his seven-and-a-half-year stay, one day he received a letter from his wife that also had a photo of her mother enclosed. Feeling confused as to why she had sent this, he also thought there must be more to it. So, what did he do? He soaked the photograph in urine to see if a message appeared – and it did. The back of the photo revealed some code that James continued to use to communicate with the Navy about the conditions at the prison.


How to make learning history fun


If your child liked learning about invisible ink, maybe they have an appetite for history. Or maybe they find learning about history to be boring and need some revving up. Here are some ways to get your child interested in this intriguing subject outside of the classroom. 🤓

  • Visit museums

A quick Google and we’re sure you will find a museum or three in your town or city. Museums are a great, interactive way to get your child interested in history that also gets them out of the house. Plus, a museum visit = family day out! 🏛️

  • Watch historical films
Combine entertainment with education and you’ve got yourself a winner. The number of history-based films on Netflix and Amazon is truly impressive. No matter what aspect of history they’re fascinated by, there’s something for all curious minds. 🎞️
  •  Get reading

When your child hears the two words "history" and "books", they probably envision page upon page of densely-written text. But that doesn’t have to be the case. There are many informative and accessible books out there that blend fun facts with exciting illustrations and interactive games. 🙌

  • Check out our blog

GoStudent loves to inform and educate without getting too heavy – consider us the smart friend you turn to when you want to learn something new! From the ins and outs of Tudor kings and queens to some need-to-know facts about ancient Egypt, keep checking our blog for more history-inspired posts that we hope will get your child’s cogs turning. ⚙️

We also have excellent tutors on hand to help your child get the best from their studies, be it history, maths, English, geography or French (plus many more!). Want to try us out? Book a free trial lesson today.

Did you and your child like this DIY video? Great! You should check out how to make your own tornado in a bottle or friendship bracelet too!