From the record
“The Crestone School, also known as the Crestone Community Building, at Cottonwood St. and Carbonate Ave. in Crestone, Colorado, was built in 1880 and was listed on the National Register of Historic Places in 1986.”
Wikipedia article Crestone School, CC BY-SA 4.0.
One of 7 National Register listings published here for Saguache County · listed in 1986 · category: Building · built in 1880.
Sources: the Wikipedia article · the case file at the National Archives · the National Register database, National Park Service