An Experiment to Evaluate the Efficacy of Cognitive Tutor Geometry

This randomized, controlled field trial estimated the causal impact of a technology-based geometry curriculum on students' geometry achievement, as well as their attitudes toward mathematics and technology. The curriculum combines learner-centered classroom pedagogy with individualized, computer-based student instruction. Conducted over a three-year period in eight high schools within an urban fringe district, the study found that students assigned to the treatment curriculum scored 19 percent of a standard deviation lower on the geometry posttest that their counterparts assigned to the district's standard curriculum, but found no statistically significant impact on students' attitudes toward mathematics and technology. Researchers also collected observation and interview data on teachers' instructional practices. These data suggest that many teachers had difficulty implementing the treatment curriculum's learner-centered pedagogy. In fact, observed levels of learner-centered practices were only modestly higher in treatment classes than in control classes. In both treatment and control classes, however, higher levels of learner-centered pedagogy were associated with higher student achievement geometry.