|M.Sc Student||Porat Gilit|
|Subject||Learning about the Meaning of Measurement in Physics through|
the Construction and Calibration of Measurement
Devices-Exposing Conceptual Difficulties
|Department||Department of Education in Science and Technology||Supervisor||Assistant Professor Shulamit )Shu Kapon|
|Full Thesis text - in Hebrew|
We developed an instructional module in which students learn about the meaning of measurement in physics through the construction and calibration of measuring devices. The goal of the study was to examine how the unique learning experience that the module provides influences the understanding of the role and process of measurement in physics, and to characterize the conceptual difficulties that were brought into the open during its iterative implementations.
The study answers the following research questions: (1) What are the design principles that characterize the instructional module, and how they evolved in response to the conceptual difficulties that the students presented in each implementation? (2) What were the conceptual difficulties that were brought into the open during the learning process?
Employing a design-based research approach, the instructional module was iteratively designed, implemented and studied in three iterations: a course for preservice physics teachers (N1 = 21) and two courses for in-service physics teachers (N2 = 19, N3=13). The characterization of the conceptual difficulties and the articulation of the changes in the design principles were pursued by: (1) a comparative analysis of the laboratory reports within and between iterations; (2) A diagnostic questionnaire that was administered before and after the second and third implementations; (3) content analysis of the conceptualization of measurement in physics as it is presented popular instructional resources (three textbooks and one video) at the high school and introductory-university levels.
The findings have theoretical and empirical contributions and implications. (1) The instructional module shows how central concepts such as measurement uncertainty and measurement error can be meaningfully discussed even at the introductory high school level. (2) The findings show that even teachers who hold a bachelor’s degree in physics or rich-physics engineering, often do not understand and cannot explain the rationale behind the technical actions they perform in data analysis, and therefore do not always perform it correctly. (3) The findings suggest that students and teachers tend to focus on the difference between the measured value and the theoretical value (measurement error) and ignore the "confidence interval" in which they can report their measurement result (uncertainty). This tendency leads to inadequate treatment of discrepancies between experiment and theory. (4) The analysis of instructional resources suggests that the use of language in all the instructional resources examined do not explicate the differences between the uncertainty of the measurement result and the measurement error. The words error and uncertainty sometimes appear as synonyms, and often the same word represents different meanings in different contexts. Moreover, we documented the use of numerus concepts related to the process of measurement without any aspects of knowledge organization that hierarchically connect them. (5) There is a need to add a chapter to the high school physics curriculum that will discuss the teaching of physics in the laboratory, additionally, high quality curricular materials should be developed. The findings cohere with recent position papers of the American Association of Physics Teachers, that criticize the quality and effectiveness of university lab courses and call for change.