ABSTRACT A case study was designed to explore how students of grade seven learn and operate with negative numbers after the concept was formally introduced in school. A focus group of nine grade seven students shared their views during group discussions on themes such as negative numbers, magnitude, zero, the number line, the minus sign and brackets. Three students from the group of nine were selected and interviewed while they worked with negative numbers. They were asked to justify the steps they used to solve each problem. There were some similarities among students of this study, results of previous research and early mathematicians. Students were unsuccessful in working with negative numbers based on their knowledge of natural numbers. Students learned to work with negative numbers with the models of rules and the number line presented to them by the teacher. They solve problems involving negative numbers through rote memorization and could not explain and fully justify their responses through higher level thinking which leads to the development of metacognitive skills. The dual role of the minus sign proved to be problematic to students as well.