Students need to arrange themselves so that they are positioned and postured to face each other for direct eye-to-eye contact and face-to-face academic conversations using "12 inch voices."
句子意思：学生们需围成圈,面对面低声交流和研讨.
12 inch voices的英文解释：
speaking quietly enough so that only people in close proximity can hear you
这里的"12 inch voices"是一种课堂上小组讨论方式,只有组内成员能听到彼此谈话,组与组之间的讨论互不干扰,12英寸 = 30.48 厘米,这里是个约数,表示只有在几十厘米范围内才能听清对方谈话内容,比喻谈话声音低而已.
与此类似的说法还有"6 inch voices"