Διδασκαλία Γεωμετρικής Οπτικής Σε Μαθητές Ε' Δημοτικού

Abstract

Literature review of studies on geometrical optics revealed that a considerable number of them into children's ideas on geometrical optics held before and after instruction.This study seeks to investigate the shift the students' ideas undergo, the difficulties students might be encountered with and the possible tasks which may help them overcome problems arising during constructive teaching. For the effective collection of data, students' worksheets completed collectively on the day of teaching, exercises they filled individually at the end of each unit, and the posttests completed individually at the end of the research were used. Our research has shown that the initial ideas pupils held on geometrical optics, with the exception of propagation of light, diverge from the scientific model; during consecutive teaching sessions most children adopted the scientific model; and the unit on coloured shadows presented a problem to students.Our study revealed that pupils adopted the scientific model for half the tasks assigned to them while they adopted a hybrid model for the rest of them. Posttests pointed out that children adopted the scientific model for half the questions. For the rest of them they adopted a hybrid model or they still resorted to their initial ideas or they even provided worse answers, compared to the ones of the pretest. One should take into account that although some students did well during teaching sessions, they did not reach the same level of performance during assignments or posttests, and vice versa.Our study concludes that children face difficulties such as the size of penubra, the extension of reflected or refracted rays and the ray crossing the lens' focus.