Scientific Practices in Elementary Classrooms: Third-Grade Students' Scientific Explanations for Seed Structure and Function

Elementary science standards emphasize that students should develop conceptual understanding of the characteristics and life cycles of plants (National Research Council, 2012), yet few studies have focused on early learners’ reasoning about seed structure and function. The purpose of this study is twofold: to (a) examine third-grade students’ formulation of explanations about seed structure and function within the context of a commercially published science unit and (b) examine their teachers’ ideas about and instructional practices to support students’ formulation of scientific explanations. Data, collected around a long-term plant investigation, included classroom observations, teacher interviews, and students’ written artifacts. Study findings suggest a link between the teachers’ ideas about scientific explanations, their instructional scaffolding, and students’ written explanations. Teachers who emphasized a single “correct explanation” rarely supported their students’ explanation-construction, either through discourse or writing. However, one teacher emphasized the importance of each student generating his/her own explanation and more frequently supported students to do so in the classroom. The evidentiary basis of her students’ written explanations was found to be much stronger than those from students in the other two classrooms. Overall, these findings indicate that teachers’ conceptions about scientific explanations are crucial to their instructional practices, which may in turn impact students’ explanation-construction.