Bostonia doesn’t seem to exist anymore, if it ever really did. A stamp on the mat says “Halliday’s Studio, Bostonia, ND.” There was a post office on a farm there from 1908 to 1913, and Halliday’s studio was probably also in a home, although the closest Halliday families I found in Census records were several counties to the east. The school in the photo was probably in a larger community than Bostonia.
The schoolhouse looks brand new and well-constructed. Curtains are hanging in the windows. An outhouse is visible just behind the main building. Winters on the plains are windy and bitterly cold, so the outhouse had to be close by.
Most of the children seem pleased to be at school and to have their picture taken. It was probably a rare event, and the day must have felt like a special occasion.
There’s a fascinating website with recent pictures of abandoned North Dakota buildings, called Ghosts of North Dakota, which may have a photo of the schoolhouse on one of its pages. I saw several school buildings that looked very similar to this one but not exactly like it.