When the weather is nice, the Buxton boarding school moves lunch outside. Students, faculty and guests grab their food from the kitchen, and eat together under a white tent that overlooks western Massachusetts’ Berkshire mountains.As the close of the school year neared last June, talk turned to final assignments (the English class was finishing Moby-Dick) and end-of-year fun (there was a trip planned to a local lake). It was, in most ways, a typical teenage afternoon – except that no one was on ...