Annick Weil-Barais

Students' Conceptions in Physics and Mathematics: Biases and Helps

Abstract The thought modes that children and adolescents develop to solve problems encountered in everyday living are analyzed from two points of view: (1) sources of systematic error in solving mathematics and physics problems, and (2) the possible factors of knowledge development in these fields. Taking into account the gaps in thought modes necessarily involved in gaining access to scientific knowledge, and considering the possible links between the initial conceptions of individuals and the conceptions of experts, the authors discuss some potential means for providing cognitive guidance to foster the development of knowledge.

Heuristic value of the notion of zone of proximal development in the study of child and adolescent construction of concepts in physics

The heuristic value of the concept ofzone of proximal development in the field of scientific instruction is demonstrated by means of a study on the construction of the concept offorce by students aged 14 and 15. Based on an analysis of the differences between the students’ intuitive concepts and those taught in school, a sequence of learning steps are proposed to allow students to achieve the “shifts” needed to receive the concept of force, defined as an interaction between systems. Acting on the zone of proximal development means taking advantage of what students already know in order to help them construct precursory concepts in preparation for new conceptual propositions. The original teaching sequence presented is based on experimental problem situations designed to promote modelling skills. Students are asked to make predictions about measurement variations. To perform these prediction tasks, they must construct new concepts and use specific representation techniques. The study enabled us to show that it is possible in ten sessions to lead students to construct a precursor for the formal concept of force.

Apprentissage de concepts en mécanique et modélisation de situations expérimentales

RésuméPartant d’une analyse des limites des travaux antérieurs relatifs à la formation des concepts „catégoriels” pour aborder la formation des concepts physiques, et d’une analyse épistémologique des concepts fondamentaux de la mécanique, une séquence d’enseignement a été conçue dans la perspective d’étudier comment de tels concepts („formels”, „relationnels”) peuvent être maîtrisés par les élèves en faisant appel à des démarches inductives et axiomatiques. L’expérimentation décrite porte sur la grandeur „quantité de mouvement”, concept introduit en première année de lycée. L’analyse de la séquence d’enseignement montre les limites de l’induction dans la construction du concept étudié; le repérage des propriétés définissant la grandeur ne s’est avéré possible que par un jeu de questions relatives aux relations établies préalablement entre des grandeurs connues des élèves (masse et vitesse). L’analyse de leurs conduites montre que l’appréhension des propriétés (transfert, invariance, additivité…) et de la relation (

Evolution of expectations of constancy of quantity of air by 10–11 years old students

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Evolution des Jugements de Conservation des Quantités de Gaz Chez des Elèves de CM2@@@Evolution of expectations of constancy of quantity of air by 10–11 years old students

) présente moins de difficulté que la maîtrise des invariants opératoires présente moins de difficulté que la maîtrise des invariants opératoires permettant l’élaboration des représentations des situations expérimentales (la sélection et le découpage temporel des événements, la partition en systémes, l’analyse des interactions…). Les ruptures dans les modes de pensée qu’imposent la prise en compte de tels invariants permettent de comprendre les difficultés des changements conceptuels.AbstractStarting from an analysis of the limits of the formation of of categorial concepts as an approach to formation of physics concepts, and an epistemological analysis of the concepts fundamental to the domain of mechanics, a teaching sequence was conceived of with as its purpose the study of how such concepts («formal» and «relational») can be mastered by pupils using inductive and axiomatic procedures. The experiment described examines the concept of momentum, introduced in the first year of the lycée. The analysis of the teaching sequence shows the limits of induction in the construction of the concept studied. The logging of properties defining this quantity showed itself to be only possible through a number of questions related to previously established relations between the quantities known to the pupils (mass and velocity). An analysis of pupils, behaviours showed that the comprehension of properties (transfer, invariance, additivity…) and of the relation (

The influence of a priori ideas on the experimental approach

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