The study aimed to investigate students' conceptions on the notion of absolute value and their abilities in applying the specific notion in routine and non-routine situations. A questionnaire was constructed and administered to 17-year-old students. Data were analysed using the hierarchical clustering of variables and the implicative method, while…

In this study, we attempt to put in question students' spontaneous and uncritical application of the simple and neat mathematical formula of linearity. This is impelled with the help of a written test involving geometrical problems, which is based on an original experimental setting. In this setting, grade 9 and 10 students were instructed first…

Presents an analysis of written solutions to geometry exercises in the last year of Greek Lyceum which showed relatively low performance on vector methods. Justifies pupils' false preconceptions with regard to the concept of vectors, and the strong influence of classical geometry teaching in the previous years. (Author/ASK)