The old classroom model simply doesn’t fit our changing needs….It’s a fundamentally passive way of learning, while the world requires more and more active processing of information.

Salman Khan, The One World Classroom (2012)

From Francis Parker to John Dewey to Ella Flagg Young, to Vito Perrone to Deborah Meier to Theodore Sizer, complaints about the “old classroom model” have echoed through university lecture halls, academic monographs, oodles of conferences and, now, in education blogs. Criticism of existing public schools has spawned generation after generation of reformers looking for ways to alter the dominant “factory model,” “assembly line,” or “batch processing” way of schooling over the past 150 years.

Their target has been the historic structure of the age-graded public school with its  buildings divided into hallways lined with box-like classrooms where teachers distribute slices of curriculum grade-by-grade using whole and small-group instruction, homework, and tests. The regime…