Using Discourse Analysis to Explore Student Understanding of Chemistry

The increased adoption of active learning strategies to teach chemistry at the undergraduate level provides a unique opportunity to investigate how students develop understanding of representations (including mathematical inscriptions) and fundamental concepts in chemistry and the nature of the classroom environment that supports (or constrains) this development. Doing so also calls for better and more refined methodological approaches.  The specific goals of this project are:

• to identify student generated arguments using Toulmin’s Model of Argumentation
• to characterize students’ conceptual level of understanding using a framework that examines how students translate between macroscopic, sub-microscopic, and symbolic levels of chemistry
• to characterize the instructor’s discursive moves using the Inquiry Oriented Discursive Moves framework to see how instructors encourage student argumentation and student translation among the representational levels of chemistry
• to analyze the nature of the POGIL materials and identify how they aid (or hinder) students in translating across levels and to what extent they encourage students to explain their chemical reasoning

In particular, we focus on the shifts of knowledge among individuals, small groups, and the whole class community, and hence on the relationship between knowledge constructed by individuals and the collective activity of the classroom community. This research is expected to lead to theoretical understanding of and methodological advances for characterizing, documenting and coordinating individual and collective progress in chemistry accomplished in classrooms with active learning environments. This project collects and interprets data about student reasoning that will inform the STEM education community about student learning.  The results of the research will provide additional insights into how instructional strategies and the design of curricular materials improve (or inhibit) student understanding of chemistry. These insights can then be applied to develop improved models for curriculum development and pedagogical strategies for chemistry and other STEM disciplines.

Figure 1: The Toulmin Model of Argumentation

To help characterize student understanding we use multiple frameworks to analyze the collected data, one such framework is Toulmin Analysis.  In his seminal work on argumentation, Toulmin created a model to describe the structure and function of certain parts of an argument. Figure 1 illustrates that, for Toulmin, the core of an argument consists of three parts: the data, the claim, and the warrant. In any argumentation, the speaker makes a claim and presents evidence or data to support that claim. Typically, the data consist of facts or procedures that lead to the conclusion that is made. To further improve the strength of the argument, speakers often provide more clarification that connects the data to the claim, which serves as a warrant, or a connector between the two. It is not uncommon, however, for rebuttals or qualifiers to arise once a claim, data, and warrant have been presented. Rebuttals and the qualifiers aid to propel the argument forward. If one disagrees with the claim, he or she may present a rebuttal, or counter-argument that shows disagreement. When this type of challenge is made, often a qualifier is provided, which is a way to provide specific conditions in which the claim is true. Finally, the argumentation may also include a backing, which demonstrates why the warrant has authority to support the data-claim pair. Genuine argumentation therefore occurs when students are involved in turn taking or cycles of conversation where each person attempts to interpret the meaning of another’s statement and adjusts his or her response.

Figure 2: Johnstone's Triangle Illustrating the Three Levels of Chemistry

To better understand how students conceptualize chemistry content we are using an analytical approach to examine how well the students are able to translate between macroscopic, sub-microscopic, and symbolic levels of representation. Our own view of reasoning regarding the chemistry triplet, as shown in Figure 2, is consistent with a sociocultural perspective on learning in which the three levels of representations can be considered part of the classroom community’s repertoire of resources for communication and representation of ideas. According to this perspective, instructors and curricular materials would be expected to have a substantial impact on students’ reasoning using macroscopic, submicroscopic, and symbolic levels of representation. Evidence thus far suggests that curricular materials in physical chemistry, such as textbooks and laboratory resources, may provide relatively little support for students to connect symbolic-level representations to macroscopic and submicroscopic ideas in physical chemistry contexts. Instructors, however, may scaffold student’s reasoning by modeling appropriate ways of coordinating macroscopic, sub-microscopic, and symbolic information or may provide hints and prompts to enable to students to make connections themselves. Reducing this support, both in terms of instructor interaction and in the support provided by instructional tasks, may allow students to develop more independence as their own conceptual frameworks and understanding of relationships between macroscopic, sub-microscopic, and symbolic levels become better integrated over time.

Figure 3: Inquiry Oriented Discursive Moves Framework

Instructor facilitation has been shown to play a critical role in students’ understanding of macroscopic, sub-microscopic, and symbolic ideas in other chemistry contexts as well. Therefore in addition to analyzing student's ability to generate arguments and their conceptual understanding, we are also interested at looking at the how an instructor influences the discourse taking place in the classroom, to do this we are using a framework know as Inquiry Oriented Discursive Moves (IODM), Figure 3.  This framework was developed to focus on aspects of argumentation not captured by Toulmin’s framework. The IODM framework addresses questions related to how a teacher’s interaction with students or peer interactions contribute to classroom learning, particularly as it relates to inquiry. Correlating the discursive moves of the instructor to the presence and quality of student arguments can provide insights into understanding effective facilitation of active learning environments. It can also be used to analyze how instructors support learning in inquiry oriented laboratories. A Revoicing discursive move is when an utterance is said again by another speaker.  Revoicing serves three functions in a class. One function is to highlight specific ideas and move the discussion forward.  A second function is to empower student thinking, and a third is to help students understand what are considered reasonable explanations.  Questioning/Requesting discursive moves are explicit questions directed to students. They serve to help reveal a student’s understanding of the material.  Telling discursive moves are characterized by information being stated or procedures defined. Telling moves are used to further discussion, direct student attention to a new task or idea, provide insight, or guide student argumentation. Managing discursive moves focus on moving the class forward but do not contain content-related information. These moves tend to focus on classroom management efforts that are employed to organize students in structural and affective ways to increase student engagement.