HR: 13:55h
AN: ED22E-02    [PDF]
TI: Dating the Earth: What Students "Think" They Know About Radioactivity
AU: * Prather, E
EM: eprather@as.arizona.edu
AF: University of Arizona, UA Astronomy Department, 933 N Cherry Ave., Tucson, AZ 85721 United States
AB: Contemporary science education research emphasizes the importance of considering students pre-instructional beliefs when designing effective, student-centered instructional strategies. When scientists teach about dating the Earth, most often the concepts of radioactive decay and half-life are presented. However, our research illustrates that students bring to the classroom many inaccurate beliefs and reasoning difficulties on the topics of ionizing radiation, radioactivity, and radioactive decay that are well-poised to interfere with students' understanding of how half-life is used to determine geologic time. In an effort to uncover the range and frequency of the dominant student beliefs with regard to radioactive phenomena, we performed individual demonstration interviews and administered open-response concept tests to students from a wide-range of science backgrounds. Our results show that students are often unable to differentiate between the ideas of irradiation and contamination, and that many of these students' reasoning difficulties about radioactive decay and half-life stem from their inaccurate mental models regarding the atom.
UR: http://shiraz.as.arizona.edu
DE: 6605 Education
SC: Education and Human Resources [ED]
MN: 2003 Fall Meeting