An overview is presented of research studies (carried out in the 1970s) dealing with the influence of time on student academic achievement. Discussions illuminate studies and findings about: (1) length of school day; (2) academic learning time; (3) achievement levels and academic time; (4) clarity of first day organization and planning; (5) time distributed across class activities; (6) interactive supportive instruction; (7) focus of instruction; (8) student understanding of lessons; and (9) curriculum and instructional strategy. In considering the reliability of research findings in these areas, it is pointed out that many of them have been used to train teachers in new modes of thinking and have produced changes in their ways of teaching. Major findings are also reported on a study examining links between school policy, leadership style, teachers' and students' attitudes, and teachers' and students' behavior. The point is made that, in the past decade, schools have been studied in isolation, classrooms in isolation from schools, and students in isolation from classrooms and school. The charge for the next decade is asserted to be to study the whole school context, taking into consideration administration, teachers, and students together. It is suggested that the results of this type of research, combined with the empirical findings generated during the 1970s, should enable the development of a comprehensive and practical theory of effective schooling. A list of 13 reference notes and 11 references is included. (JD)