Second-Grade Students' Use of Written Explanations in the Context of Model-Based Inquiry

• In Event: 45.027 - Supporting Elementary and Middle School Students to Write Scientific Explanations

Abstract

Purpose
This study is part of the Modeling in Primary Grades (MPG) project that examines second grade students’ learning about matter through model-based inquiry. We examined the role that students’ explanations played in contributing to the public or shared knowledge of the classroom. Further, we studied the development of students’ knowledge about phase changes of matter as reflected in their written explanations, constructed during learning.

Theoretical Framework
Developing students’ facility with the use of models to investigate and explain scientific phenomena is emphasized in the NGSS (2013) reform documents. Prior research indicates that model-based inquiry can serve as a productive framework for science instruction in the early grades (Lehrer & Schauble, 2018; Manz, 2012). From a model-based inquiry perspective, we regard scientific explanation as the modeling of physical mechanisms that underlie a target phenomenon (Darden, 2007). We design inquiry environments to scaffold students’ construction of model mechanisms to explain material phenomena.

Methods
This is a mixed-methods longitudinal study of second grade students (n=92) from five Mid-Western, public school classrooms that implemented the MPG curriculum as part of their routine science instruction (see Authors, 2017 for a description of the curriculum). MPG teachers received professional development to use written and dialogic scaffolds to facilitate students’ learning. Cognitive science techniques of quantitative content analysis (Authors, 2017; Chi, 1997) and qualitative interpretive techniques (Ryan & Bernard, 2000) were used to analyze data.

Data Sources
The primary data sources were science notebook records of individual students’ written explanations, developed in the context of investigations of phase changes such as melting (solid to liquid), freezing (liquid to solid), and evaporation (liquid to gas). Additionally, videotapes of class discussions were analyzed to contextualize how the written explanations contributed to students’ joint sense-making during the co-construction of knowledge.

Results
Our analyses of classroom discourse indicate that MPG students organically used written explanations in the building of public or shared knowledge, actively referring to their own and their peers’ representations in class discussions, and borrowing diagrammatic and linguistic conventions from each other to modify their explanations. Furthermore, the students showed significant growth in explaining macroscopic changes observed in phase transitions in terms of the arrangement and movement of constituent microscopic particles.

Significance
Our findings indicate that model-based inquiry can support young students’ use of abstract physical mechanisms to explain material phenomena. Explanation writing is effective when contextualized organically in the inquiry practices that are used to support the co-construction of shared knowledge by students.

Acknowledgments
This research was supported by a grant (#122853) from the National Science Foundation. The opinions expressed are those of the authors and do not represent views of the National Science Foundation.

Authors

• Ala Samarapungavan, Purdue University

• Lynn A. Bryan, Purdue University

• Jamison Wills, Purdue University