the actual distance was
There are 9 public schools in Caroline County today.
In 1875 there were 49 schools. The average distance between them was 2.24 miles as the crow flies *.
Even for the most isolated locations near the edges of the county (X), the nearest school was about 3 miles away. And there may have been closer schools in adjacent counties.
Use the map here to compare school locations in the 1875 map of Caroline County to modern satellite imagery. Locations in imagery are only approximate; they have not been field checked. If you visit, send me a note about what you found.
* I used QGIS opensource software to digitize the 1875 school locations shown 1875 John B. Isler map of Caroline County. I used ArcGIS software to calculate Nearest Neighbor, Euclidean distance. More careful analysis for this purpose would exclude short distances between clustered schools in Denton and Federalsburg. This would increase slightly the average distance between schools.