This page will provide information about findings from the Evaluating DMI study. As of summer, 2012, we have begun to analyze data from our first year of study:
New DMI Classroom Video Assessment (CVA)
We worked with Advisor Nicole Kersting (U AZ) to create a new measure of teacher knowledge grounded in classroom practice. The DMI Number and Operations CVA uses 3-5 minute classroom video clips as stimuli for teacher reflection on how teachers and students interact around DMI-related content (counting and operations using whole numbers, decimals and fractions). Responses are scored using four 3-point rubrics (Mathematical Content; Student Thinking; Suggestions for Improvement; and Depth of Interpretation) with inter-rater reliability between 0.85 and 0.90. We piloted 18 clips with 21 teachers, then chose 11 based on psychometric properties and differentiation between more or less sophisticated responses.
DMI-Based Knowledge Gains on the Learning Math for Teaching (LMT) MKT Measure
Teachers in both Treatment and Comparison groups took the Learning Math for Teaching (LMT) assessment of Mathematical Knowledge for Teaching (MKT) both before and after the DMI seminars. Initial results show a statistically significant difference in LMT gain scores for teachers in DMI seminars (0.43, SE=0.11) compared with the control group (–0.08, SE=0.15); F(1, 39)=14.70, p=0.001.
We are currently coding results from the CVA and an open-ended teacher knowledge measure, as well as classroom videotapes, student assessments, and professional development logs.