Is it scrap paper or a hidden message?
Updated: Oct 7, 2019
After watching bits of the fictitious movie "National Treasure" the class wanted to explore messages with lemon juice. Our supplies were:
1) bottle of lemon juice concentrate
2) copy paper
3) Q tips
The students were given directions written in a simple Cesar Cipher that had been taught previously. Once they had decoded the instructions, they began writing their messages. We let the messages dry over night. I opted to use the old school method of using heat from a candle to warm the message enough to view. As this method can result in fire, all of the normal precautions found in a science lab should be used: safety goggles and some form of fire extinguishing such as sand, fire blanket or a fire extinguisher. In our case, our safety supplies were safety goggles and a fire extinguisher.
The downsides of this method include time and the REAL possibility of destroying the message as it might catch on fire-which we did much the the students delight! Thank goodness we had also opted to add to our safety precautions to go outside to a paved area to conduct our enlightening experience.
FYI, we did attempt to use a blow dryer as shown in the movie. It did not work with the type of paper and "secret ink" that we used.