This study aims at elaborating a well-established theoretical framework that distinguishes three modes of thinking in linear algebra: the analytic-arithmetic, the synthetic-geometric, and the analytic-structural mode. It describes and analyzes the bundle of signs produced by an engineering student during an interview, where she was asked to recall…

Presents a model of rational number using pairs of line segments which can embody ratios of numbers. Actions upon these segments can embody arithmetical operations. Discusses tasks in a computer environment for bringing out diverse algebraic and geometric meanings of rational numbers. (Contains 23 references.) (MKR/Author)

Freudenthal was the founder of realistic mathematics education, in which reality serves as a source of applications and learning. Takes a newspaper article about reproducing a Van Gogh painting using plants in a field to exemplify a rich context problem containing elements of all areas of elementary school mathematics. (MDH)