06/10/2026
SINGAPORE — A group of secondary school students were left stunned this week after discovering an ancient classroom device capable of sharing a teacher’s screen without Wi-Fi, Bluetooth, AirPlay or even a software update.
The mysterious machine, known to historians as an “overhead projector”, was discovered inside a school storeroom alongside other archaeological artefacts including transparency sheets, whiteboard markers and a television mounted on a trolley.
Students initially assumed the device was an early 3D printer.
“So where do you connect your laptop?” asked 14-year-old Jayden Tan, examining the machine carefully.
“You don't,” his teacher replied.
“Then how does it connect to the screen?”
“It shines light at the wall.”
Jayden reportedly remained stunned for several seconds.
According to teachers, the device uses an astonishingly simple technology in which a piece of transparent plastic is placed on top of a very bright light.
Whatever is written on the plastic then appears on the wall.
Students were even more disturbed to discover that teachers could write directly onto the transparency while presenting.
“Wait, so it's touchscreen?” asked one student.
“No.”
“But you're touching it.”
“Yes.”
“And it's updating on the screen?”
“Yes.”
“But there's no Wi-Fi?”
“No.”
At this point, several students reportedly gathered around the projector in complete silence.
One later described the experience as “actually quite advanced”.
The demonstration ended when a student asked whether the overhead projector supported Google Slides.
The teacher placed another transparency on top.
“Now it does.”
