How Changing Class Size Affects Classrooms and Students Douglas E. Mitchell & Sara Ann Beach, 1990 5 pages. Abstract This policy brief is based on prior class size research and addresses the following issues of concern to policy makers: (1) the extent and reliability of class size impact on student achievement; (2) the mechanisms by which class size changes turn into student learning effects; and (3) the economic consequences of the reduction of class size. This synthesis of available research supported by a meta-analysis of achievement data shows that class size has a substantial and cumulative effect on student learning. Theoretically, the view that teachers represent a "fixed instructional resource" with their time and attention divided among the total number of students in the classroom best fits the research data. The conclusion is reached, however, that responding to this evidence is difficult because the cost of class size reduction is enormous. It is impossible to imagine public support for the level of funding needed to substantially reduce class size through expansion of school facilities and staff. Alternative strategies for reducing instructional group size can be implemented. The most promising strategy is the redeployment of existing school staff for part or all of the school day.