Workers stumbled on to a vintage surprise last week at Emerson High School in Oklahoma City.
While removing chalkboards to make way for new whiteboards, they found handwritten lesson plans datingback to 1917.
The writings were found in four separate classrooms, which took Emerson Principal Sherry Kishore aback. She remarked at the quality of the penmanship: "Some of the handwriting is beautiful," she told the the Oklahoman.
Some show mathematical methods that had been lost to time. “I have never seen that technique in my life,” Kishore said of the multiplication circle.
All four of the classrooms also had lessons on the pilgrims.
Kishore speculated that some of the drawings appear to be from students as well.
"Their names are here; I don't know whether they were students in charge that day that got to do the special chores, or if they were the ones that had a little extra to do because they were acting up." she said.