No girls allowed

Black History Month | Single-sex schools help African-American boys succeed—but remain controversial | Mark Bergin

Glen Clisham pauses momentarily from an arithmetic lesson and raises his voice above the escalating racket of 15 boisterous first-graders: "I'm going to wait until I have quiet." The room's volume drops to a murmur. Clisham, a fourth-year teacher at Thurgood Marshall Elementary in Seattle, resumes instructing, satisfied with something less than total silence.

Some students stand as they listen. Others sway side to side or fiddle with the various papers and craft supplies strewn across their desks. In many first-grade classrooms, such behavior might draw correction. Not here. Clisham's higher tolerance for noise and movement is based on the premise that traditional expectations of perfect posture and sealed lips may hinder learning for these young boys.