In this article, a study focusing on the perceptions and motivations of middle school students in physical education classes is described. The Physical Education Learning Environment Scale (PELES) was developed to measure student perceptions of learning environment, or class climate, in physical education on dimensions of perceived challenge, perceived threat to sense of self, perceived competitiveness, and perceived control. The PELES was administered, together with the Intrinsic Motivation Inventory (IMI) to a sample (N = 622) of middle school students. Exploratory factor analyses provided evidence of adequate construct validity for the PELES, following elimination of the perceived control subscale. Multiple regression analyses indicated that perceived threat and perceived challenge predicted intrinsic motivation for both males and females. These findings are discussed in terms of their implications for practicing teachers and for future research.