Brother & Sister?

Since my mom recently retired after a long and distinguished teaching career and my wife is now on school vacation, I thought I would post this nice cabinet card photo of what appears to be a brother and sister, or classmates at the very least, in front of their schoolhouse during the late nineteenth century. Unfortunately, there is no notation on the back, but I did purchase this one in Northwood, NH, so it could be from New England originally. They seem to be dressed up, so one wonders if this was a special occasion, perhaps a graduation day. Anyway, I very much like this image of two kids and wonder where life took them after their school days...