Design and refinement of an introductory teaching-learning sequence in quantum physics

In this paper we report on the process of designing, testing, and refining an introductory teaching-learning sequence (TLS) in quantum physics based on Feynman’s sum over paths approach. The sequence is explicitly designed taking into account the “framework theories” perspective on conceptual change, and aims at overcoming known alternative conceptions and difficulties reported in the literature in the learning of basic elements of quantum physics. In particular, results concerning the concepts of “wave particle duality” (which in Feynman’s approach is spoiled of most of its dualist character) and the uncertainty principle are thoroughly investigated. The sequence was first tested in the context of a teacher training course. Results of this first test were encouraging, and showed the students to be able to achieve an expert-like language in a very short time. Writings produced in the final test showed clear signs of appropriation by students of the subject matter. However, the first test also showed some limitations, concerning mainly students’ understanding of the uncertainty principle. Furthermore, we felt that in view of a test in high school, the sequence had to be expanded in both the experimental and metacognitive dimensions; and also the number of examples that were analysed quantitatively had to be expanded, to connect our treatment with the exercises present in usual textbooks, and the requirements of the Italian curriculum. The final version of the sequence was tested both with student teachers and directly in class, in the final year of a science-oriented high school. We present the results for both the intermediate and final test, and report on the redesign process and our provisional conclusions.