Investigated the effectiveness of an experimental mathematics teaching program. The treatment program was primarily based on a naturalistic study of 40 relatively effective 4th-grade mathematics teachers. Students were tested before and after with a standardized test and a content test (posttest only), which had been designed to approximate the actual instructional content that students had received during the treatment. Observational measures revealed that teachers generally implemented the treatment, and analyses of product data showed that students of treatment teachers generally outperformed those of control teachers on both the standardized and content tests. Since strong efforts were made to control for Hawthorne effects, it seems reasonable to conclude that teachers and/or teaching methods can exert a significant difference on student progress in mathematics. (4 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved). © 1979 American Psychological Association.
