THE MORAL LIFE OF SCHOOLS, by Philip Jackson, Robert Boostrom, and David Hansen. (JosseyBass, $28.95.) For two and a half years, three Midwestern professors of education meticulously observed 18 elementary and high school teachers, hoping to understand how these teachers, albeit in less than a fully conscious way, created particular moral climates in their classrooms. Noting everything from the sudden raw edge in a teacher's voice to the seemingly offhand gesture, the authors came to believe that virtually everything a teacher says or does is fraught with moral significance. Quoting Ralph Waldo Emerson, they write: "Character teaches above our wills. Men imagine that they communicate their virtue or vice only by overt actions and do not see that virtue or vice emits a breath every moment.'' Indeed, the authors convincingly argue that morality in schools has less to do with object lessons than with nuance--the residue, so to speak, of everyday life. Is the teacher who praises all students' writings with equal enthusiasm building pride or indicating, even if unintentionally, that quality doesn't really matter? Is the teacher who addresses a noisy 1st grader with "Richard! Are you visiting or helping?'' being disingenuous--she knows he's in fact misbehaving--or is she, as the authors suggest, "inviting her students to take a third-person perspective on their own actions...which might be read as the first step toward self-criticism.'' Is the English teacher who responds to the principal's booming loudspeaker announcement on the perils of tardiness by falling backward and clasping her hand to her heart being overdramatic or taking on "the attitude of mock deference that many of today's nonviolent protesters have learned to adopt?'' These are admittedly subtle questions but far from inconsequential, for teaching is a subtle craft, full of small confusions. Whether teachers like it or not, the authors insist, everything they do affects their students, which is why the observed teachers are correct when they say, "We teach ourselves.'' Who we are, this invaluable book reminds us, imbues our teaching, which is why good teaching--that is, moral teaching--must begin with self-scrutiny.