The purpose of this paper is to summarize and evaluate experiments which examined the effects of teacher questions on student achievement. The studies reviewed are of two types: (a) training experiments, in which the independent variable is teacher training; and (b) skills experiments, in which the frequency and manner of use of a teaching skill is prescribed by the experimenter. The first section of this paper presents brief overviews of both training and skills experiments. Each overview lists (a) grade, (b) subject, (c) independent variable, (d) dependent measure, (e) teaching time, (f) analysis and results, (g) comments, and (h) conclusions. The second section discusses the experiments and presents suggestions for improving the quality of research on teaching. These suggestions include the following areas: (a) reporting the study, (b) design, (c) analysis, (d) dependent measures, and (e) general questions of method. The last section presents conclusions gathered from the studies reviewed and warns of misleading research supported by superficial claims of valid methodology. (PB)