In a traditional classroom arrangement—with the teacher lecturing at the front of the class—"the group becomes homogenized," Silverman says. The teacher targets the instruction to the middle, ignoring the passive, inattentive students in the back and the more advanced students who might be bored because they already know the material.
The teacher might ask two to four students to come to the front of the room to solve a problem, but the rest are "educational voyeurs," he says.