From the record
“The Ingersoll School, a one-room schoolhouse near Washburn, North Dakota, was built in 1885. It was listed on the National Register of Historic Places in 2010.”
Wikipedia article Ingersoll School, CC BY-SA 4.0.
One of 8 National Register listings published here for McLean County · listed in 2010 · category: Building.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service