An overview is presented of research findings on how teacher expectations of student performance may alter the ways that teachers treat students, and the possible negative effects of such differential treatment on the behavior and learning of students for whom the teacher holds low expectations. A discussion follows on the teaching implications of research findings that point to effective ways to improve student performance. Findings are discussed on the topics of: (1) when and how to praise students; (2) the effective use of questions; and (3) student seat assignments in the classroom. Brief descriptions are offered of five exemplary teacher inservice programs focusing on teacher expectations. References are included. (JD)