Identifying and Resolving Problematic Student Reasoning About Ionizing Radiation

Abstract

The Radioactivity By Inquiry Project is developing an inquiry-based radiation curriculum for teaching radiation literacy at the high school and college levels. Researchers for this project have found that students’ initial ideas about radiation are problematic for comprehending the characteristics and effects of radiation. For example, students initially do not distinguish between radiation and the radioactive source. In an earlier study, Eijkelhof1 clearly identified undifferentiated radiation concepts among Dutch high school students. The undifferentiated view is that radiation is “bad stuff”, that there is no difference between radiation and radioactivity, and that radiation causes contamination. The goal of the radiation materials is for students to develop a more sophisticated view of radiation as high-speed, subatomic particles. Such a view distinguishes between radiation and radioactive materials and enables thinking about mechanisms of radiation emission and interaction with matter. Problems arise as students develop the subatomic particle view - for example, many try to hang on to the contamination idea of radiation.

This study builds on the research of Eijkelhof to identify and characterize students’ initial ideas about radiation in terms of Eijkelhof’s undifferentiated radiation concept. This paper identifies the three facets in which 90% of the students in the trial course developed more sophisticated ways of understanding the scientific view of radiation, characterizes the learning gains, and discusses necessity of a conceptual change in order to develop these new models of thinking. Using a phenomenological approach2, the researchers have inferred student reasoning on radiation - from the beginning to the end of the course materials - as expressed in conversations, observations, video recordings, interviews, and class work. The Radiation By Inquiry project is supported by NSF DUE grant 0942699. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation or of Black Hills State University.