The project will research the effectiveness of new information and communication technologies in teaching various scientific and mathematical concepts at secondary level. The project focuses in particular on the analysis of complex data. We will use and adapt innovative instructional material and analyze students' competencies by means of classroom observations and clinical interviews. The interactive constitution of meaning in classroom discourse will be analyzed by means of new interpretative methods of research into classroom interactions. Our goal is to identify and describe more precisely various conceptual barriers that make statistical reasoning difficult for secondary students and to develop and test an instructional sequence that would enable such reasoning at a rudimentary, but statistically valid, level. The project is situated in the context of interdisciplinary research in mathematics education (didactics of mathematics) with relations to the didactics of the sciences.