Chalkboard drawings are made to be erased, but a set of them at an Oklahoma City high school managed to outlive all the teachers and students involved.

Workers at Emerson High School removing old chalkboards were amazed to find another set of chalkboards underneath that had not been touched since 1917, the Oklahoman reports.

The drawing and writing on the boards appear to date from Thanksgiving of that year, with many of the lessons having Pilgrim themes, reports the Washington Post.

"I give my head, my heart, and my life to my God, and one nation, indivisible, with justice for all," reads the pledge written on one board.

Staff members say they found it very moving to see the work of their predecessors from nearly 100 years ago. "Well, first of all I got goosebumps, and then I got tears in my eyes," Principal Sherry Kishore tells Fox 25.

"And then I sat in here and just stared because it's really like walking into a time capsule. When you walk into these rooms, it's like they just left the lesson and they're expecting to come back the next day and start again." The school district says it plans to find a way to preserve the boards.

(Last year, the "Steve Jobs Time Capsule" yielded items that included a Moody Blues eight-track.)

This article originally appeared on Newser: Behind Chalkboard, an Enchanting Century-Old Find

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