Three separate, sequential three-month studies were made to determine the effects of timed pupil feedback on teaching behavior. Audiotapes were made of the teaching behaviors of eighteen teachers before, during, and after the teachers introduced a feedback instrument to their pupils. The tapes were analyzed for changes in teacher behavior over the period of time the feedback was used. The results indicated that student feedback did change the teaching behavior significantly. The general direction of change was toward less teacher talk and lecture. The questioning techniques of teachers stayed fairly constant with the only statistically significant change being in the mean number of questions asked each month. The conclusions were that students can give accurate feedback which effects change in teacher behavior and that this change can be described and quantified using interaction analysis techniques. (Author/JY)