I’d read about this schoolhouse in “Hudson Valley Ruins. Forgotten Landmarks of an American Landscape. ” by Thomas E. Rinaldi and Robert J. Yasinsac where it’s described as follows:

District No. 8 School, McKeel Corners. Built c. 1875, this fine example of a country schoolhouse stands about two miles east of Cold Spring near the northeast corner of the intersection of what was once known as the Albany Post Road and the Cold Spring-Carmel Turnpike. The hilly area surrounding the school once supported active farms. Many of these were abandoned over the course of the nineteenth century as industrialization and westward migration led to a downturn in agriculture that was particularly felt in Putnam County. Schools like this continued to serve the families that remained until centralization in the twentieth century caused many of these archetypal building to be abandoned. In 1996 the state Office of Parks, Recreation and Historic Preservation acquired the building and the land around it. Now part of the Clarence Fahnestock Memorial State Park, the schoolhouse remains empty…”

For some reason I had difficulty finding it despite the quite precise directions. I thought it was farther south than it is, and back in the woods. It’s actually right on the east side of Route 9 (The Albany Post Road mentioned) a little north of the intersection with Route 301 (The Cold Spring – Carmel Turnpike mentioned).