The purpose of this study was to determine the relationship between teacher fitness and teacher/student interaction in the classroom. Eighteen experienced high school teachers volunteered as subjects. Subjects were divided into high-fit (HF) and low-fit (LF) categories by comparison with norms for their age and sex in sit-ups, sit-and-reach, percent body fat, and maximal aerobic power. Teacher/student classroom interaction was evaluated by coding audiotapes with the verbal portion of Cheffers’ Adaptation of Flanders’ Interaction Analysis System (CAFIAS). It was revealed that HF teachers spent less time asking questions and more time giving directions than LF teachers. Teachers initiated talk more in the morning, especially on Monday, and students talked more in the afternoon, especially on Friday. Students initiated more talk in the afternoon and were more unpredictable and noncontent oriented in both their initiated and responding behavior in the afternoon. There were no significant interactions between fitness level, day, and time. The current evidence does not support the hypothesis that physically fit teachers are clearly distinguishable from unfit teachers in terms of teacher/student interaction.