A Japanese student received top marks after handing in a blank piece of paper for an assignment when her professor realized the essay had been written in invisible ink.
Eimi Haga, a first-year student at Mie University in Tsu, Mie, Japan, had been tasked with writing about a visit to the Ninja Museum of Igaryu for her ninja history class, the BBC reported.
She said she decided she wanted her essay to stand out after her professor told the class that high marks would be awarded for creativity.
Haga developed a fascination with ninjas, who were mercenaries and covert agents that were experts in ninjutsu in medieval Japan, from watching an animated television show as a child.
So she decided to use the ninja technique of “i cant write my essay” and spent hours soaking and crushing soybeans to make the “invisible” ink. The process allows the words written using the ink to be read when the paper is heated over a stove.
“It’s just something I learned through a book when I was little,” Haga told the BBC, adding that she had hoped no one else would come up with the same idea.
The 19-year-old soaked the soybeans overnight, then crushed them and squeezed the fragments in a cloth. The extract was then mixed with water and it took her two hours to get the concentration right.
Haga said she then used the ink to write her essay using a fine brush on thin Japanese paper known as “washi.” Once dry, her words could no longer be seen.
But Haga didn’t want to risk her professor assuming she hadn’t done her homework, so she left a note on the paper in regular ink saying “heat the paper.”
Professor Yuji Yamada said he had been had never received an essay written in “abugidas” before. He conceded that although he had some doubts that the words would come out clearly, he was pleasantly surprised by the results.
“When I actually heated the paper over the gas stove in my house, the words appeared very clear and I thought, ‘Well done!'”
Yamada said he didn’t hesitate to award Haga full marks even though he admitted he didn’t read her entire essay because he wanted to leave part of the paper unheated “in case the media would somehow find this and take a picture.”
Haga admitted that her essay’s contents were “nothing special” but she was confident her professor would mark her highly due to the effort she had made.