A study was conducted to investigate the relationship between teaching style and within-term changes in the motivation of two-year college students. "The Echelle de Motivation en Education" (Academic Motivation Scale was administered to 1,597 female and 837 male students at a junior college in Quebec at the beginning of the term and again 3 months later. Teaching style was measured using the Teaching Style Inventory, which identified dominant, auxiliary, back-up, and least-used styles of teaching behaviors to create a teaching profile. Five teaching styles were identified: outcomes oriented; empathic and people oriented; intellectually oriented; innovatively oriented; and mixed teaching style. Findings revealed that highly structured, well-organized, and outcomes-oriented junior college teachers seemed to maintain student motivation, whereas autonomy-supportive and people-oriented teachers were likely to decrease student motivation. The change in student motivation observed in the groups where the teachers had a mixed teaching style supported the idea that versatility in teaching is essential. (Contains 82 references.) (KP)