School transitions and educational innovations confront students with changes in their learning environment. Though expectations are known to influence perceptions and motivation, which, in turn, influence the effectiveness of any situation, students' expectations for a new learning environment have received little attention. This longitudinal survey, conducted with 1,335 high school students (average age, 15 years), studied students' expectations and subsequent perceptions of 5 characteristics of a new environment (fascinating content, productive learning, student autonomy, interaction, and clarity of goals) and the students' (prospective) dissatisfaction. Results showed that expectations were positively related to later perceptions. Also, high prospective dissatisfaction was related to higher actual dissatisfaction with the environment later on. Investigating expectations and prospective dissatisfaction in relation to student characteristics (i.e., motivational orientations; conceptions of learning; strategies for regulation, information processing, and affective processing) show that motivational problems and fear of failure were risk factors for educational innovations. Furthermore, students' disappointment with the new environment was related to undesirable changes in student characteristics, such as increased fear of failure. The findings stress the importance of preparing students for curricular changes. (Contains 1 figure and 8 tables.)