Heat Transfer Conceptions Used in an Engineering Design-Based STEM Integration Unit: A Case of Struggle

Abstract

In the United States, there has been an increased emphasis on science, technology, engineering, and mathematics (STEM), and especially engineering, in pre-college settings. There are several potential benefits of this, including: increasing the quantity and diversity of students who pursue STEM careers, improving all students’ technological literacy, and improving student learning in the STEM disciplines. While current standards support the integration of the four STEM disciplines in pre-college classrooms, research still needs to be done to determine which models of STEM integration are effective and how and why they impact student learning. The context of this study is a model of STEM integration called engineering design-based STEM integration. The purpose of this study was to do an in-depth exploration of students’ use of science conceptions during an engineering design-based STEM integration unit, with additional focus on how engineering design, redesign, teamwork, and communication influence students’ use of science conceptions. For this study, the unit was designed to address middle school-level physical science concepts related to heat transfer, including temperature, thermal energy, and processes of heat transfer (i.e., conduction, convection, and radiation).An embedded case study design was used to explore students’ science conceptions while they participated in an engineering design STEM integration unit. The case was one student team from a seventh-grade science class, and the students within the team were the embedded sub-units. Data were collected on each day of the unit’s implementation; these data included video of the student team and entire classroom, audio of the student team, observations and field notes, and student artifacts, including their engineering notebooks. Data were analyzed primarily using methods from qualitative content analysis. Themes emerged for the whole team, with emphasis on specific students when appropriate.The results show that there were a few key features of engineering (i.e., engineering design, redesign, teamwork, and communication) that influenced students’ use of heat transfer conceptions. During much of the problem scoping stage, which included the science lessons focused on heat transfer, students mostly used scientific conceptions about conduction, convection, and radiation. However, when they needed to think about those three processes of heat transfer together, as well as apply them to the context of the engineering design challenge, the students began to use a larger mix of scientific conceptions and alternative conceptions. Several alternative conceptions emerged when they combined ideas and vocabulary from conduction and radiation to create one set of rules about thermal properties of materials (i.e., did not distinguish between conduction and radiation). Even when they used scientific conceptions, the students sometimes applied the conceptions unscientifically when designing, which led them to create a prototype that performed poorly. However, the student team then learned from the failures of their first design and redesigned, during which they appropriately used mostly scientific conceptions. In other words, the opportunity to learn from failure and redesign was critical to this team’s use of correct conceptions about heat transfer. Two other features of engineering that emerged were teamwork and communication through notebooks. Students on the team learned from each other, but they learned both scientific and alternative conceptions from each other and from their peers on other teams. Engineering notebooks proved to be somewhat helpful to students, since they referred to them a few times when designing, but more importantly they were helpful in revealing students’ conceptions, especially for one student on the team who rarely spoke.The findings of this study contribute to future development and implementation of other engineering design-based STEM integration curricula because they show how various features of engineering influenced this student team’s use of science conceptions. In particular, the results demonstrate the importance of giving students the opportunity to learn from failure and redesign, since this process can help students use more scientific conceptions and potentially repair their alternative conceptions. Additionally, it is important for curriculum developers and teachers to think carefully about the transition from problem scoping to solution generation and how to include effective scaffolds for students to help them combine their conceptions from science lessons and apply them correctly when designing. These results also have implications related to heat transfer conceptions, as the student team in this study demonstrated some scientific and alternative conceptions that were already in the literature. Additionally, they used alternative conceptions when they confused concepts from conduction and radiation, which are not in literature about pre-college heat transfer conceptions. These findings suggest that more research should be done to explore the interaction of engineering design and students’ science conceptions, especially heat transfer conceptions.