This project was designed to help students find an answer to the question, “What happens in a simple electrical circuit?” using conductive wire, a light bulb and a battery, in the context of the new science and technology program in the second-tier primary education curriculum. The purpose of the project was, with the help of the example of a simple electrical circuit, to discover the relationship between what students perceived and what they conceptualized in their minds. The study was undertaken in two schools in the province of Samsun, Turkey with a sampling of 428 students in the 6th (n:163), 7th (n:119) and 8th (n:146) grades. The common trend in the findings of the qualitative data analysis may be summarized as follows: It was found that students had difficulty interpreting events or phenomena that occurred simultaneously, that they were prone to easily substitute one concept for another, that they preferred to substitute mental models in place of scientific models in the case of unobservable phenomena and as a result, that the construction in their minds of the concepts of energy and electricity remained confused and disconnected. The study suggests that scientific models may be used in both supporting a basic concept of the electrical circuit rather than the idea of the simple circuit, and in analyzing the relationship between concepts of energy and electricity, particularly in the case of unobservable phenomena.