The author reports on an investigation on concept of area in classes of French 6th, 7th and 8th grade. The questionnaire, which was developed to this effect, deals with two subjects: 1.) Up to which extent is concept of area involved in questions not referring explicitly to this concept. 2.) Up to which extent are certain methods involved which have been introduced in order to represent areas, i.e. for example tiling for area mensuration, square lattices for comparison of areas, using the fact that a rectangle is divided into two triangles of some area by its diagonal. The analysis of the results of this investigation is preceeded by a study of the concept of area from a psychological point of view and in relation to its presentation in textbooks. (ZDM/Mathdi)