Schnittka and Bell (2011)
This US study investigates the impact of engineering design activities on 71 students' conceptions of 'heat transfer' and 'thermal energy'. It compares strategies to demonstrate conceptual change.
- Using an 'engineering design' curriculum in conjunction with directly addressing naive conceptions was effective for promoting conceptual change.
- Structure is required to bridge the gap between an engineering design problem and the science content which supports it.
- Engineering design activities alone are not enough to promote deep conceptual change.
- Students often describe thermal energy transfer in terms of ‘cold’. They identify a flow of coldness to and from substances causing them to change temperature or freeze.
- Students picture heat as a flow of a substance, using terms such as “heat always rises”.
- Students may describe materials as being naturally warm or cold. For example, wood and plastic are warmer than metal. They may also think metals naturally trap or absorb cold.
- Students associate some materials as being a cause of heating or warmth. For example, sweaters, blankets, or socks generate heat.
- Students have an unclear concept of heat, associating it only with something that is always warm or hot.
- Students have vague ideas about absorption, describing dark objects as attracting heat.
- Using the word 'engineering' in engineering design can intimidate some teachers. Calling this a 'design curriculum' may be better in some circumstances.
Three research questions are explored:
- What are students’ conceptions about thermal energy and heat transfer before instruction?
- How do students’ conceptions about thermal energy and heat transfer change after instruction in each of the three treatments?
- How do the three instructional approaches compare in promoting conceptual change?
Three classes were taught using different instructional methods. The efficacy of these methods for promoting conceptual change was assessed using pre- and post-intervention testing. Representative subsets of each class were selected for interviews pre- and post-instruction. Classroom observations were also conducted.
The two instructional methods used in non-control classes were developed by Schnittka, Bell & Richards (2010). Five of the twelve questions in the pre- and post-instruction test were based upon questions from the 26-item thermal concept evaluation (TCE) developed by Yeo & Zadnik (2001). The remaining seven questions were developed by the authors based on research-based alternative conceptions from Driver et al. (1994), Erickson & Tiberghien (1985) and Lewis & Linn (1994).
Results were analysed by comparing statistical values computed from pre- and post-instruction test scores.
Details of the sample
The sample contained 71 students from three eight grade (age 12-13) classes taught by the same teacher in a suburban public school in the Mid-Atlantic region of the USA. The classes were statistically equivalent in terms of their state math and reading scores from seventh grade.
Driver, R., et al. (1994), Constructing Scientific Knowledge in the Classroom, Educational Researcher, 23, 5-12.
Erickson, G. and Tiberghien, A. (1985), Heat and temperature Children's ldeas in Science ed, Philadelphia: Open University Press.
Lewis, E.L. and Linn, M.C. (1994), Heat energy and temperature concepts of adolescents, adults, and experts: Implications for curricular improvements. J. Res. Sci. Teach., 31, 657-677.
Yeo, S. and Zadnik, M. (2001), Introductory thermal concept evaluation: Assessing students' understanding, The Physics Teacher, 39, 496-504.