This study is based on the achievement goal theory and intended to verify the effects of the motivational climate of the physical education (PE) on students' motivation, interest, and intention to practice physical activity or sport. In order to meet these objectives, 975 participants, from 13 to 18 years of age, completed the following instruments: PECCS, TEOSQ, IMI, Satisfaction Scale, and the Intention to Practice Physical Activity or Sport. The data were analyzed by means of Structural Equation Modeling (SEM). The results confirmed that the mastery dimension of motivational climate has an influence, directly or indirectly, on task orientation, the three dimensions of intrinsic motivation¿interest, perceived competence, and satisfaction¿and the intention to practice physical activity or sport, in contrast to ego orientation. On the other hand, the comparison dimension of the motivational climate demonstrated specific effects on each of the variables analyzed, increasing the tension-pressure and negatively affecting the enjoyment and interest of the students. Therefore, in PE, a motivational climate oriented more toward mastery, rather than a competitive climate, should be promoted.