Scaffolding High School Students’ Reasoning on a Multifactorial Trait in Genome Sciences

• In Event: Toward a Refined Understanding of Social and Material Scaffolds in STEM Education

Abstract

Objectives
Public interest in genetics is increasing as articles linking genes to human behavior and health are discussed by the major news media (BBC, 2009). These accounts often exaggerate the role of the identified gene in causing a particular condition, ignoring the fact that other genetic and environmental factors may also contribute to it (The Times, 2005). In addition, many studies may only indicate an association between a gene and the behavior or disease, but not necessarily demonstrate causality. Although experts may interpret the scientific results accurately, scientific findings and arguments are often not intuitive to non-experts (Roth & Barton, 2004). The authors have developed learning resources and scaffolds to engage high school students in an inquiry project to investigate the factors that influence a multifactorial trait, smoking behavior. The goal of this design-based research study (Bell, 2004) is to understand the student reasoning about the complex relationships between genetic/environmental factors and smoking.

Theoretical framework
In this study, the authors focus on student “reasoning” during hypothesis development and testing (Lawson, Oehrtman, & Jensen, 2007) and the “scaffolding” that guided their inquiry and learning (Pea, 2004). The curriculum allows students to develop and test their hypotheses driven by their own interest and observations within an unmined database derived from an original case control study. More specifically, students identify database items related to their overarching hypothesis, develop specific hypotheses and conduct statistical tests, interpret the results with odds ratio and confidence interval calculations followed by causality checks, and construct arguments and present their findings to others. Accordingly, our analysis focuses on a) students’ patterns of reasoning and the sources of their hypotheses, b) the ways in which students construct arguments based on statistical evidence, and c) how our scaffolding guides their inquiry and understanding of a multifactorial trait.

Methodology
From the first year of implementation, our data sources include field notes and video- and audio- recordings of thirteen student groups’ database activities from three public high schools and a local summer program in the Pacific Northwest. Each group consisted of 2-4 high school students and they were ethnically and culturally diverse. The authors analyzed the data and identified noteworthy themes using microgenetic analysis (Taylor & Cox, 1997). The authors will discuss the nature and issues of students’ reasoning and the embedded scaffolding with literature.

Findings
Preliminary analysis suggests that students: a) develop their hypotheses from their everyday beliefs and observations and b) develop their understanding of statistical concepts as they test hypotheses and seek relevant resources to understand the concepts. However, it also indicates that c) students tend to violate the nature of hypothesis testing by revising their hypotheses to agree with the evidence when it does not support the original hypothesis but indicates a different conclusion, or conducting multiple tests before developing a well-formulated hypothesis.

Scholarly significance
This study will contribute to scholarship on students’ hypothetical reasoning and associated curriculum design issues.

Authors

• Hiroki Oura, Waseda University

• Katie Van Horne, University of Washington

• Maureen Munn, University of Washington

• Andrew W. Shouse, University of Washington