Natural Editing of Algebraic Expressions

Long version of a communication at MathUI workshop, Linz, Austria, June 2007.We call “natural editing of algebraic expressions” the editing of algebraic expressions in their natural representation, the one that is used on paper and blackboard. This is an issue we have investigated in the Aplusix project, a project which develops a system aiming at helping students to learn algebra. The paper summarises first this project. Second it defines the notion of algebraic expression, and of representation of algebraic expression. After an exploration of 20 software systems which represent and edit algebraic expressions, the idea of natural editing of algebraic expressions (insertion, deletion, selection, cut, copy, paste, drag and drop) is presented, leading to the notion of “smart editor”