The picture reads Alder High 1917, so this may be the entire high school.
In 1909 a four-room school house was built in Alder. In 1913 they added a gymnasium.
From left to right are: Bill Marek, Ruth Swanson (teacher), Curtis Hedborg, Grace Parks, Elizabeth Hotes, Margret Hotes and Einar Carlson.
Photo courtesy of Pat Van Eaton.
Click on image to enlarge.