Emerson Mid-High School Principal Sherry Kishore is starting to feel a lot like a time traveler.

Twice since June, work crews renovating the historic school in downtown Oklahoma City uncovered slate blackboards with well-preserved drawings dating back nearly 100 years.

The latest discovery was made while students were on winter break. Once again, Kishore was among the first to witness history.

"It's like you're walking into a time capsule that's been preserved," Kishore said Friday. "It's like you just walked through the door into another generation."