Based on Inglehart's (1997) idea that the importance of modern values is challenged by a growing importance of postmodern values in postindustrialised societies, we analyse the consequences of students' attempts to integrate (modern) achievement values and (postmodern) well-being values. Since opportunities for value integration are limited, students should frequently experience conflicts, whether to work for school or to engage in free time activities. In a questionnaire study, students (n = 184) showed mostly high scores in both, achievement and well-being values. Value conflict--measured by a specific conflict formula--was related to the frequency of action conflicts as well as to the reported difficulty to decide which action to pursue. Values predicted the students' school-related decisions. Furthermore, students with high achievement values reported better performance in school-related tasks than students with high well-being values. Finally, values were systematically related to time investment and grades. (Contains 4 tables and 1 note.)