The methodology employed during physical education sessions can determine students’ motivations and implicit beliefs about their own abilities. The aim of the present study was based on comparing the effects produced on motivation and implicit beliefs about self ability when implementing a Sports Education model and a traditional style. Ninety-three secondary education students participated in the study, with ages ranging from 13 to 15 (13.32 ± 0.62). A total of 54 students took part in the sessions designed according to the Sports Education model and 43 in those following a traditional style. At the beginning and the end of the didactic unit, each student was administered the questionnaire CMEF (Cuestionario de Motivación en Educación Física) for motivation in physical education and the questionnaire Conceptions of the Nature of Athletic Ability Questionnaire-2 (CNAAQ-2) for implicit beliefs about ability. Results showed significant differences for the Sports Education model in the dimensions of intrinsic motivation, identified regulation, introproyected regulation, and external regulation (p < 0.01). The Sports Education model is optimal to promote motivation; therefore, teachers should consider putting it into practice as a methodology to improve students’ motivation profile.