Second Edition Findings

The second edition of Investigations in Number, Data and Space became available for full-year implementation during the 2007-2008 school year.

During the multi-year research and development process that resulted in the second edition, a team of outside evaluators from Indiana University worked with the Investigations authors to study the impact of pre-publication materials on student learning. The research was large scale (using data from three different geographical regions with multiple classrooms at each site), longitudinal (examining impact on the same students over three years of schooling), and comparative (including matched comparison groups for grades 3 through 5 at two of the sites). Study measures included both standardized tests (national and state) and neutral tests designed by the researchers. The researcher-designed items focused on the content most heavily impacted by the revision process—number, operations, and algebraic thinking.

Did the revised materials have the intended impact on student learning? Although high student attrition rates at some of the sites limited the use of more powerful statistical analyses of the longitudinal effects on student achievement, single-grade comparative analyses of the data showed that Investigations students did as well or significantly better than comparison students using other curricula on both standardized tests of mathematical achievement and on researcher-designed assessments. At one site the Investigations students outperformed the comparison group at each grade level and at the other site they performed statistically the same.

This study should be viewed as a first step towards understanding the impact of the second edition. Several factors limit conclusions that can be drawn from this study. The curricular materials were not in final form, measures of classroom practice were based on self-report, and high attrition rates limited the power and complexity of the statistical analyses. However, the results do provide evidence of efficacy. Future research should examine contextual factors that may maximize impact of the 2nd Edition on student learning and instructional practice.

This research is described in the 2007 report What Did They Learn?: A Longitudinal, Comparative, and Focused Study of a Prepublication Version of Investigations in Number, Data, and Space by Paul Kehle, Kathy Essex, Diana Lambdin, and Kelly McCormick.