Invisible Ink Decoder
Decoding invisible ink is an important tool used by law enforcement to solve crimes related to espionage and counterfeiting rings. Of course, it can also be a fun activity for kids. Try incorporating it into a scavenger hunt with friends and family.
Write secret messages using "invisible ink." Have a child dip a cotton swab in lemon juice and write or draw on plain white paper. To make the design appear, hold the paper to the sun or near a hot light bulb. Supervise children as they do this just in case.