Secondary school students' strategies in solving combination problems

International audienceThis work is part of a wider investigation conducted in Italy, which aims to explore the effects of instruction in combinatorial reasoning of secondary school students. Two groups of students with and without instruction were given a questionnaire adapted from Navarro-Pelayo's research in order to analyze the students' performances and strategies used in the solutions, as well as the effect of instruction. In this work we present the results found in three combination problems. The students did not generally present particular difficulties in solving problems of combinations even though students who received instruction showed an improvement in their performances. In the no instruction group enumeration was the main strategy while the group of instruction used a more heterogeneous distribution of strategies