Abstract:
In this article, the researcher will report on methods for scoring concept maps to assess conceptual change in preservice elementary teachers’ understanding of the concept of density. The researcher used the method of Total Proposition Accuracy (TPA) scoring to assess conceptual understanding of density prior to and post instruction. The researcher categorized students’ misconceptions about density as either spontaneous or scientific concepts using Vygotsky’s (1987) theory of concept development. The researcher used a paired sample t-test analysis and determined that after instructional intervention, students demonstrated statistically significant improvement from pre- to post-concept maps (t = -2.89, p = .005). Some spontaneous concepts that appeared on pre-concept maps were either reduced or eliminated on post-concept maps; other spontaneous concepts proved to be more robust and persisted after intervention. Although small, statistically significant gains were noted in the t-test analysis; these findings suggest that elementary preservice teachers’ content knowledge about density is weak; the average TPA score after receiving instruction was one proposition (n = 56), and many teachers continued to hold the same misconceptions post-instruction as did other K–12 students who participated in other studies. After receiving instructional intervention, the majority of students who participated in this study used the emerging concept of the density formula (67%) to define density, and others (30%) used procedural information that was featured in the lesson activities. The two robust misconceptions about density related to confusing density and buoyancy to explain the phenomena of floating and sinking (42%) and confusing density with heaviness, mass, and weight (23%). Only 4% of students used the scientific definition of property of matter to define density correctly. These results suggest that teachers have well-developed idiosyncratic conceptions about density that will take considerable time and effort to reduce or eliminate. Based on the results of this research, the researcher recommends that teacher training programs help preservice teachers improve their elementary content knowledge about density by focusing on the Archimedes principle during content course instruction.
