Elementary Students’ Understanding about How Convex Lenses Affect Light Propagation

Abstract

In the present study, K-3 and K-4 students’ understanding of the effects that convex lenses have on light propagation is investigated. Specifically, the study examines the extent to which these students are able to construct a scientifically accepted explanation for the role convex lenses play in converging rays of light and creating inverted images in the case of both self-luminous and hetero-luminous objects. Eight students from two primary schools run by the Municipality of Piraeus in the region of Attica (Greece), took part in the survey. They were divided into groups of two. The research was conducted using the teaching experiment method, which combines elements of the clinical interview and formal teaching. According to the results, students of this age recognise the convergence of light as a process that takes place through a convex lens. However, they have difficulty attributing the aforementioned convergence to the light refraction that takes place during the interaction of the light beams with the converging lens. At the same time, while they can easily ascertain that light beams continue along the same straight line after the convergence point, they find it difficult to relate this conclusion to the creation of an inverted image of a hetero-luminous object.