Enseignement apprentissage de la chimie : Construction du concept de mole en classe de 3ème de l’enseignement général au Cameroun par la démarche d’investigation comme mode de transposition didactique.

Abstract

In Cameroon, the concept of the mole is introduced for the first time in the third year of secondary school (ages 12-14). Learning this concept poses a challenge for students at this level, especially when they have to interpret its literal meaning. This research aims to measure the impact of inquiry-based remediation on the scores of third-year students in General Secondary Education. To achieve our objective, a two-level, multiple-choice questionnaire was administered as a pre-test to 431 students to identify their difficulties and their origins when they have to conceptualize the concept of the mole. The results obtained, based on the choices made in the first level and the analysis of the students' responses during the pre-test phase, show that students encounter difficulties when conceptualizing the mole. These difficulties are linked to a lack of knowledge and alternative interpretations. Among these misconceptions, we observed: conceptual confusion between molecular molar mass and atomic molar mass, between atomic molar mass and the number of atoms, between atomic molar mass and the atomic number, and between the amount of substance and mass. We also noted the students' inability to apply the formula for calculating the number of atoms. This study also compared the frequency of correct answers at the first level, combined with an analysis of justifications in the post-test, between two groups (99 students each). The experimental group underwent remediation involving an inquiry-based approach, while the control group received remediation using a standard approach. The post-test results showed an average rate of 38.87% in the control group compared to 81.5% in the experimental group for the eight two-level questions. These rates were reinforced by good justifications at the second level. In question 9, the average success rate in the control group was 28.5% compared to 61.5% in the experimental group. Remediation involving inquiry-based learning significantly improved academic performance on the concept of mole. Thus, we can conclude that learning based on inquiry-based learning as a method of didactic transposition helps learners overcome their difficulties.