Many one room, one teacher rural schools were built on land donated by ranchers around San Luis Obispo County years before land was deeded and school districts were created. One was called Sand Hill School because the area was nothing but sand. The Sand Hill name was changed and it became Sunny Side School District in 1891.
A local rancher, John Peterson, donated property in 1875 and built a schoolhouse creating the Sand Hill School District. He built it for his daughter, Annie Peterson, who was just 5-years-old when she attended the first class.
The privately owned Sunny Side schoolhouse and the ‘teacher reach’ building that housed teachers can still be seen at its original site on the south side of Los Osos Valley on the Shong property.
Mary Boardman and her husband, George, along with their three children bought the two-acre property that included the schoolhouse in 1969.
The Boardmans collected bits and pieces of the school’s history over the years, when former students from around the state would occasionally drop by—some returning several times. They told of their early education in a one-room school. Mary discovered that many families in the Los Osos Valley area attended Sunny Side School. George Souza stopped by one day in 1976 and told Mary that his father, a sheepherder, came to the states in 1873 from the Azores and had paid taxes in the Sand Hill School District. George attended Sand Hill School from 1901-1905.
I was privileged to be a member of La Canada de Los Osos History Group (1992-1997) , when Mary invited us to hold events inside the schoolhouse in the 1990s.

Reference: “One Room Rural Schools in the Valley of the Bears” by Joan Sullivan, 2009