Researchers have studied the affects of class size on student achievement for years. Therefore, the size of classes presently is disturbing. In regards to class size reductions, Murphy, 1998 states that students enjoyed significantly greater improvements in test scores in reading, language arts, and math. A class size research study was conducted based on several reliable constructs, including the CSR program, mode of instruction, financial aspects, classroom and student affects, mathematics achievement, language teaching, and reading achievement. A quantitative research design was used in a sample of 20 middle school teachers between the ages of 25 and 55. Teachers filled out a background information sheet and a seven-question survey. The data was then analyzed to reveal that most teachers strongly agreed or agreed that smaller class sizes increase student achievement in a variety of areas. Based on literature findings and data generated, most participants agreed with the theory that smaller class sizes do increase student achievement. However, it was not determined how many other factors affect class size, such as mode of instruction. It is recommended that future research be conducted that will collaborate the importance of class size on student achievement. The following are appended: (1) Class Size Questionnaire; (2) Human Subjects Form; (3) Informed Consent Form; (4) Acknowledgement and Consent Form; (5) Human Subject Approval Letter; (6) Background Information Sheet; and (7) Final Summary Form. (Contains 15 figures.) [Master's Thesis, Marygrove College.]