Middle School Students' Mechanistic Explanation About Trait Expression in Rice Plants During a Technology-Enhanced Science Inquiry Investigation

We examined the sophistication of middle school students' mechanistic explanations of genetics phenomena and how they interact with a technology-based explanation tool as they articulate and organize their ideas about the phenomena. We coordinated curriculum and assessment design frameworks to develop a middle school curriculum unit that engages middle school students in the interrelated science practices of using models and constructing scientific explanations of the trait expression mechanism in rice plants. In order to more clearly distinguish between groups of students, specifically partial mechanistic and mechanistic explainers, we conducted a design-based research study that examines the relationships among the explanation tool's design, how students use the tool, and the sophistication of their scientific explanations. This study, using a refined version of the curriculum unit and explanation tool, revealed significant differences between partial mechanistic and mechanistic explainers in their use of the explanation tool. The findings inform the design of technology-based scaffolds for scientific modeling and explanation and design principles for gathering formative evidence of students' proficiency with these practices.