How did Light Acquire a Velocity?

We discuss how light acquired a velocity through history, from the ancient Greeks to the early modern era. Combining abstract debates, models of light, practical needs, planned research and chance, this history illustrates several key points that should be brought out in science education.     

Typology of students at risk of dropping out of school: Description by personal, family and school factors

The purpose of this study was to identify the different subgroups of students at risk of dropping out of school. The typology was developed based on the three main contexts associated with school dropout risk, namely, the personal, family and school contexts. On the basis of these factors, the clustering results enabled us to categorize at-risk students into four subgroups: (1) the Anti-Social Covert behavior type, (2) the Uninterested in school type, (3) the School and Social Adjustment Difficulties type, and (4) the Depressive type. Moreover, considering all the contexts involved in school dropout, the clustering technique confirms the importance of behavior problems and learning difficulties, while emphasizing the significance of both depression and the family and classroom environments in the development of dropout risk. Students at risk of dropping out of school report many family organisational problems and that they obtain little emotional support from their parents. They also perceive little order or organisation in the classroom.     

Ordering and structuring ideas in text: From conceptual organization to linguistic formulation

The goal of this study was to analyze the development of the relationship between conceptual and linguistic processes as regards idea ordering and structuring (linearizing), when composing a text. Participants (from 7^th graders to University students) were required to compose a text using a list of eleven scrambled ideas. Conceptual rules allow to a priori determine an optimal ordering of these ideas. Results showed a significant increase, with grade level, in the establishment of the postulated conceptual order, and in the linguistic elaboration of the text structure. A large autonomy was observed between conceptual and linguistic processes. The discussion considers the following points: The relevance of the notion of text optimal order; the unequal development with grade level of the varied linguistic skills; the dissymmetry in conceptual-linguistic relationships; the usefulness of the experimental paradigm; some consequences for education.     

Evidence of repeated access to immediate verbal memory during handwriting

Writing is a relatively slow process. A certain degree of overlapping must therefore be assumed to exist between motor activities and more «central» processes involved in the production of language. The present experiment was based on the assumption that these management processes must leave some traces at the level of execution. Subjects were asked to read and memorize a sequence of three words (examples: «parachute parapluie paramètre», «taximètre décimètre paramètre»); and write them down on a graphic tablet. The results are consistent with the following ideas:

1. the same motor program was used for the three occurrences of repeated morphemes
2. Non-repeated morphemes were recovered from verbal memory while the preceding repeated morpheme was being written.

     

L'evolution des chances d'acces a l'enseignement superieur en France (1962–1966)

The article presents the final conclusions of a series of studies (secondary analyses of statistical data and investigations) carried out by the Centre de Sociologie Européenne between 1964 and 1967 and re-evaluated in the light of the new trends which emerged after 1968 (more open system of education offset by diversification of schemes of study with unequal returns in terms of career openings or prestige). In order to present the problem of the democratisation of higher education by reference to unambiguous data, the authors propose a simple principle for calculating the opportunities for entry to a given level of instruction, or into a given field, as a function of social origin and sex. This systematic method of measuring inequality of academic opportunity, linked to sociological variables, has (a) technical (b) methodological and (c) theoretical advantages.o li](a) From the technical point of view, this calculation which relates the number of students (of a given level) possessing certain social characteristics with the cohort of young people of the same age possessing the same social characteristics, makes it possible to eliminate the ambiguities and statistical fallacies of most analyses of the democratisation of education, which are confined to a comparison of the percentages (or the change over time of the percentages) of different social categories represented within the student population, without taking account of the numerical representation (and the change over time of the numerical representation) of these same categories in the active population. li](b) From the methodological point of view, one has thus at one's disposal an indisputable method of presenting unambiguous conclusions with regard to the chronological development of academic inequalities for a given country, or with regard to international comparisons. li](c) From the theoretical viewpoint, this method translates into statistical terms a principle of sociological theory of much more general application and one which is exemplified in the article; this principle, which might be termed structuralist, states that no value (quantitative or qualitative) should be appraised in itself and for itself, rather that it must always be evaluated in its operational or transformational context by taking into account its positional value in the whole system of relations which link it to other values.By applying this principle, it becomes clear that the sciences are not, in France, more democratic than other fields of study, as is asserted by some authors who are content to compare the percentage of working-class students in the science faculties with the percentage achieved in the other faculties, without relating this rate to the extremely low one for working-class students in the Grandes Écoles scientifiques (the École Polytechnique, etc.): in fact, making such a comparison would highlight the weak positional value of scientific subjects in universities in the total system of scientific institutions of higher education and it would reveal the function of relegation (or reduced acceptance) of children from lower-class families assumed by the science faculties in a system dominated by the Grandes Écoles.On a more general level, this principle of relational intelligibility guides the authors' interpretation of opportunity for entry to higher education in France from 1962 to 1966. During this period, the structure of academic inequalities which in 1962 ranged from one chance in 100 (for the least favoured category) to 50 chances in 100 (for the most highly favoured category) has moved upwards, since, in 1966, the range of opportunities extends roughly from 2% to more than 70%. In other words, the total increase in the rate of enrolment in higher education of 18 to 21 year olds has been distributed, grosso modo, between the different social categories in proportion to existing inequalities. Despite a slight statistical narrowing of this range, the authors' psychosociological analysis attempts to show that the general system of expectations and attitudes of different social classes vis-à-vis the University cannot have been modified by a change which amounts to an upward translation of the structure of inequalities. It is therefore concluded that the policy of increasing enrolment during this period had an almost zero effect (sociologically speaking) on the phenomenon of the democratisation of the university, defined as a process equalising the academic opportunities of different social categories.Again it is the same principle, applied to the analysis of the relative scarcity of academic qualifications, which makes it possible to demonstrate that the expansion of higher education devalues degrees (both in the job market and in the symbolic prestige market) as it democratises them, thus reconstructing again at a higher level, or in fields of study yielding high returns, the academic privileges of the favoured classes.