An overview of research on elementary secondary classroom teaching presents a synthesis of findings from large-scale, classroom-based studies on teacher effectiveness. Three sets of major research efforts, dealing with classroom management and organization, systematic instruction, and effective instruction, were selected for review. Certain variables appeared to relate to student achievement: (1) work-oriented learning environment; (2) sufficient amount of time allocated to academic tasks; (3) warm and supportive classroom environment; (4) well-organized classroom; (5) close monitoring of students and active teacher participation; (6) quick teacher response to misbehavior; (7) systematic instruction pattern involving careful preparation of students for new material; (8) reasonably brisk instructional pace coupled with active information giving and receiving between teacher and students; (9) consistent teacher feedback on student performance; (10) opportunity for individual practice but with this individual time limited so that students stay actively involved with the class; (11) teacher encouragement of interactions where students are expected to participate and be challenged but still be successful; and (12) carefully organized instructional activities to both motivate students and provide appropriate practice in the lesson. Selected variables from these studies are documented in tabular form, and a profile is presented of an effective teacher. Lists of 11 reference notes and 11 references are included. (JD)