Twenty pairs of eyes eagerly converge on Jennifer Larcey as the afternoon science lesson gets under way at Bassett Elementary in suburban Cleveland, Ohio. Sure, the transfixed first-graders are salivating at the prospect of examining--and tasting--the physical properties of peanuts, raisins and M&Ms.; But something else is riveting the kids, even as Larcey stands to the side of the room issuing directions: the breathtaking clarity of her voice. "Feel the peanuts, and try to describe the texture," she instructs.
Larcey is one of seven teachers at Bassett who are, in effect, wired for sound. Nearly every word to her students is...