A historical study of applying a new perspective on mathematical concepts for improving education of “mentally handicapped” children

The law of 14 March 1973, in Luxembourg, authorized the creation of institutes et services d’éducation différencié. This law entitled children who could not follow the ordinary schools for the reason of having mental, behavioural or sensorial peculiarities to access appropriate education. However, since the school year of 1970-71, a group of mathematics and primary school teachers in Luxembourg started an experiment to use the approaches of modern mathematics in teaching mathematics to children with Intellectual Disability who had no success during 3-4 years of being in normal schools. The leader of this experiment was Robert Dieschbourg, a math teacher active in the adaptation of the New Math reform in Luxembourg. This experiment was a point of interest both for Luxembourgian communities who were seeking equality in education, and the international promoters of New Math reform. According to the reports that Dieschbourg published at least once a year, the result of the experiment was satisfactory. Two major points that can be concluded from these reports were: it is possible that “mentally handicapped” children learn maths; and modern mathematics with its “humanistic aspect” (Dieschbourg, 1971) is an answer to the question of how to include children with intellectual disability. The paper reviews how these experiments tried to show that a different approach of teaching could make “disable” children able to learn. I also use the opportunity to ask whether this experiment could show how much the mental disability was a consequence of the social construction of knowledge and the definition of being disable in achieving that knowledge. Moreover, the paper shows how the experiment was started as a part of the adaptation of the New Math curriculum, and its “successful” result was meant to support the arguments and reasoning for the implication of the bigger project of the New Math reform.