Development and Validation of the Learning Progression-based Assessment of Molecular Genetics (LPA-MG)

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We describe the development and validation of the Learning Progression-based Assessment of Molecular Genetics (LPA-MG) in a high school context. Items were constructed based on a current learning progression framework for molecular genetics (Shea & Duncan, 2013; Todd & Kenyon, 2015). The 34-item instrument, which was tied to 12 progression constructs, was administered to 65 high school students at three time points across a 23-week period of instruction. The LPA-MG, its 12 constructs, and 34 items demonstrated high reliability and construct validity with respect to the Rasch model as indicated by satisfactory fit. Further, it demonstrated utility in providing both quantitative and qualitative information around how students moved along each construct. Using a repeated measures ANOVA design, we found that students made gains across the 23 weeks that were both large and significant at the 95% confidence level. Students also moved along each construct in qualitatively meaningful ways during the 23 weeks of instruction.


This was presented at the National Association for Research in Science Teaching Annual Conference in Baltimore, MD in April of 2016.