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Teaching of colour in elementary science courses The , by Savage. John Murray. Modern Science Memoirs. Teaching science to the ordinary pupil, by Laybourn and Bailey. University of London Press.
Because of its ubiquitous nature, the textbook can almost be assumed to play at least a minor and possibly a major role in preparing students for their chosen academic career.
Textbooks are chosen, to a greater or lesser degree, because of the contents, examples, problems and activities incorporated in the text. Hence it is important to consider these different dimensions when analyzing a textbook.
In the case of the current research article, the focus will be specially on the iconographic nature of these dimensions, with scientific content providing a context for the icons. The analysis of science textbooks can provide important information not only on trends in the construction and dissemination of scientific knowledge, but also on its teaching and learning. The aim of this paper is to identify trends in the teaching of chemistry during the twentieth century from an iconographic and textual analysis of college general chemistry textbooks 1 most widely adopted in Brazilian universities.
Research Design Textbook Selection and CharacterizationGiven the large number of published chemistry textbooks, the extent to which a textbook was used in Brazilian universities in the period was chosen as the selection criterion. During the opening conference of the International Symposium on Textbooks, held in Sao Paulo in Choppin established four crucial criteria in assessing the spread of textbooks: its publishing life, the number of editions, the presence in libraries, and the availability in used book stores.
These two universities were chosen because they were pioneers in chemical education in Brazil. The selection led to the set of 31 textbooks listed in Table 1. Iconographic and Textual Analysis of the TextbooksThe following aspects were considered for analysis: 1 iconographic-all the illustrations were analyzed and categorized, and 2 textual-presentation texts were also analyzed, since authors outline their aims and strategies in them.
Given the continuous interplay between text and image, the reading of specific portions of the textbook was also essential in order to understand the purpose of the analyzed illustrations. The images were classified according to the chemical content to which the image was related. Formal aspects of the image such as its arrangement, presentation, and semantics were not included in the scope of this study.
It should be noted that in some cases, the prefaces of earlier editions were also examined. Some textbooks originally published in the USA contained prefaces in English and Portuguese, usually written by a professor from a Brazilian university. In such cases, all versions of prefaces in the introductory texts were analyzed. For both the iconographic and the textual analysis, the methodological framework adopted was the content analysis proposed by Bardin The analysis of the prefaces was conducted qualitatively and the analysis of the illustrations was conducted quantitatively.
The combination of both analyses led to the identification of different trends for the teaching of chemistry from the point of view of the textbook. Identifying and Characterizing Trends in Teaching ChemistryThe data obtained, with the proposed categorizations, were tabulated and plotted in graphical form.
The emphasis on different kinds of illustrations and chemical processes across the twentieth century enabled one to make certain conclusions relating to the trends in the teaching of chemistry across the century.
The identified trends were contextualized using the textbook prefaces where authors present their educational philosophy and the curricular trends that influenced the construction of the text. Journal articles, particularly from the Journal of Chemical Education related to the chemistry curriculum, were also used in the contextualization process. Trends in Chemical Education Through Textbooks: ResultsFrom the perspective of the exploratory analysis mentioned above, nine categories of images or illustrations were proposed: 1 laboratory and experimentation, 2 industry and production, 3 graphs and diagrams, 4 illustrations related to daily life, 5 models, 6 illustrations related to the history of science, 7 pictures or diagrams of animal, vegetable or mineral samples, 8 analogies, and 9 concepts of physics.
The figures below illustrate the categories Figs. Table 1 General chemistry textbooks used in Brazilian universities in the twentieth century and selected for analysis in this paperThe emphasis on certain kinds of images, and the resultant categorization, suggested some trends in the teaching of chemistry and, on certain occasions, the kinds of chemistry concepts considered important.
Featuring the Textbooks Which Circulated in BrazilThe period between and was marked by the circulation of textbooks originated from different nationalities in Brazil. Textbooks from France, Germany, Spain, USA and Brazil were analyzed, and different conceptions about chemical education could be observed. One can observe an example of this by comparing the descriptive and experimental approach of French textbooks characterized by the predominance of the category ''laboratory and experimentation'', with the applied and practical approach of USA textbooks characterized by the emphasis on the category ''industry and production'' followed by ''laboratory and experimentation'', and the mathematical approach of German textbooks Boll , c blast furnace Masterton Analysis of Twentieth Century Textbooks Used in Brazilian Context characterized by the dominance of the category ''graphs and diagrams'', as shown in Table 2.
It was surprising to realize that, in spite of the peripheral position of Brazil in the production of chemical knowledge, textbooks produced by Brazilian authors had an identity of their own. The compilation of the knowledge produced abroad did not occur without significant changes imposed by the teaching style prevalent at the time in Brazil.
The same was not so noticeable, for example, in the Spanish textbook Puig that, despite presenting some interesting features in respect to representations of the structure of matter, bears a clear French influence, especially from Troost's textbook. Textbooks produced by Brazilian authors showed little or nothing in common with the others, considering the aspects studied in this research.
Brazilian-originated textbooks were Fig. The economics of book production through printers who would not have had the resources or machinery to compete with publishers elsewhere, the lack of access to the printing technology available and some characteristics of the teaching in that period constitute a possible explanation for this observation. As far as the characteristics of the teaching style are concerned, the medieval scholastic tradition, which emphasized classical and intellectual studies to the detriment of manual work and practical activities, continued to prevail in Portugal well into the middle of the eighteenth century despite its fading influence in the remainder of Western Europe.
Jesuit education was prevalent in Brazil until , when the Society of Jesus was expelled from the Colony by the Portuguese government. However, the process of organizing the first lay Ribeiro stated that, Its mostly religious aim, its literary content, the methodology of the lower courses Humanities , which culminated in the movement called imitation … and the methodology of the higher courses Philosophy and Theology , subordinated to 'scholasticism', led professional clergymen, and intellectuals in general, to turn away not only from other religious orientations, but also from the newborn scientific spirit … This is because the search for a new method of knowledge, characteristic of modern science, originates from the recognition of the shortcomings of the medieval scholastic method, adopted by the Jesuits Ribeiro , p.
Also, according to Ribeiro, even with the creation of the first degree courses in Brazil between and , the study of different areas of knowledge was still following the same rhetorical, literary patterns instead of the scientific ones.
In reality, school organization in Brazil in the period from to was marked by the permanence of dichotomies between intellectual and practical work, word and action Ribeiro Given the diversity of the nationalities associated with the textbooks circulating in Brazil until the late s, as well as the diversity of views on the teaching of chemistry itself, talk about ''trends'' seems to be a little presumptuous.
These factors, coupled with difficult access to textbooks in Brazil at the beginning of the twentieth century Souza et al. On studying the different style and content of the chemistry presented in textbooks, some historians of science advocate the existence of regional and national differences in style of scientific thinking and working rather than the emergence of what one might call an international science resulting from technical advances in communication and transport.
Different from the idea of stereotypes, a national style can be defined as a set of persistent features from a specific nation or culture that affect their actions towards knowledge, development of scientific research or the organizational and social nature of scientific institutions Reingold Nye's research, for example, deals with the dichotomies between the development of chemistry in France and England in the nineteenth and early twentieth centuries.
Considering that it is possible to identify different ways of thinking and practising science, textbooks can constitute an important tool in this endeavor, since they host the ''disciplinary consensus'' of a period over time. We agree with Hallewell , who points out that, … it is difficult to imagine an activity that involves so many aspects of national life as the publication of books. The book exists to give literary expression to the ideological and cultural values. Its graphical presentation is the meeting point of aesthetics and technology.
Its production requires the availability of certain industrial products … Its sale is a business process conditioned Deming , b financial balance Holmes , c analogy to the topic stoichiometry, including the concepts of reactants, products, excess and limiting reactants Kotz by geographical, economic, educational, social and political factors.
And the whole provides an excellent measure of the degree of dependence or independence, both from the spiritual as material standpoint Hallewell , pp. In fact, among the 20 works considered representative of the period between and , only two did not originate in the USA. However, it was not until the first half of the s that the technical-consumerist aspects of the American model attracted more attention in Brazil than the fascinating and apparently very promising German model.
The main instruments used by the Americans were radio and cinema. However, Quintaneiro points out that, in the context of a Brazilian higher education dominated mainly by French and German literature, an important cultural diffusion step would be ''the distribution of technical books and manuals, translated to Portuguese … to university students'' Quintaneiro , p. However, the massive influx of American literature in Brazil which took place from the s significantly changed the higher education landscape.
In the late s, the Brazilian university system was under severe criticism which led to the mobilization of both the Government and the academic community in favor of the necessary reforms Paula The American agency provided assistance in the form of seminars, courses and consultancies, whose aim was to develop the different levels of education in Brazil. The agreement also included the distribution of free textbooks to primary schools and the improved access of tertiary students to technical books.
Besides the changes in cultural influences, the content of chemistry textbooks was also influenced by changes in chemical knowledge and in conceptions about science education, as revealed by the distribution of the analyzed illustrations among the proposed categories. The first mentioned period was responsible for a total of 2, illustrations and that number rose to 5, in the second period , totaling 7, analyzed illustrations.
Although the highest number of textbooks analyzed was for the second period, Fig. There was a remarkable shift in priorities of representation, especially from the practical emphasis to the theoretical, with a marked decrease in the number of images associated with experimentation and industry, and a corresponding increase in models and representations of Cartesian-type plots. This shift seems to have occurred in the transition from the s to , extending to the s, as shown in Figs.
The stress on principles is made necessary because the facts of chemistry-properties and uses of chemical substances-have accumulated so rapidly that no one can hope to remember them except as they are summarized by the underlying principles … descriptive facts should be introduced only as they correlate with principles Tamres and Bailar , p.
From this perspective, the content of descriptive chemistry assumed a more illustrative character, whose importance would be to exemplify the true body of chemical knowledge: concepts and principles.
The greater emphasis on principles, and on its application to explain and predict the properties of substances and the occurrence of chemical phenomena seems to have had an impact on the nature of the illustrations used in textbooks as shown in Fig.
In addition, the trend in the use of illustrations that combine a chemical phenomenon with a model association between phenomenological and theoretical-conceptual levels of comprehension used to explain it across the decades of the twentieth century is shown in Fig.
The early use of such illustrations in portraying the content of chemistry can be seen in the work of Nernst, published in , and it wasn't until the late s that there was a noticeable rise in the use of such illustrations for describing chemical processes and concepts.
This trend can be seen in Fig. The percentages were calculated taking the total number of illustrations for each period Fig. Regarding the objectives for the war and post-war period, an analysis of the Journal of Chemical Education publications revealed a series of articles showing the strong influence of industry on College curricula.
This influence can be traced back to the s the first issue of this journal was published in , when several articles emphasized the important role of chemistry in industry, but seems to have been intensified in the post-war period. In the s and s, several communications discussed expectations and needs of industry, and proposed a closer relationship between chemistry curricula and the interests of the chemical industry White ;du Pont ;Willard ;Robertson ;Moore ;Hauser ;Rinenart ;Quill ;Murphy Skills and abilities that should be developed were presented by White in the article ''chemical industry and the curriculum'' as follows.
Thirty years ago ability to make analyses was the most important end. Now … the plant laboratory is no longer a goal. The worthwhile fields are in research, development and operation. All of these fields demand an ability to apply general laws to new conditions. Mathematics and physics should be emphasized … Laboratory work in chemistry should be restricted, and principles and problems stressed White White , p.
The education of chemists who were reflective and capable of creative endeavour over and above repetitive procedures as important as they were became even more necessary in the post-war period when the success of the chemical industry opened various unique job opportunities for chemists Quill These new jobs demanded qualified personnel to promote the progress of the country Hauser Quill expressed his concern for the education of chemists as follows.
The success of many chemical projects in the winning of the war effort served to glamorize chemistry. Young people register for training in our profession because it is thought there will be a great need for chemists in these immediate future years.
However, most of these people are not qualified to become chemists-they are better suitable to be trained as laboratorians or technicians Quill , p. As mentioned, the unprecedented advancement of chemical knowledge was also responsible for the reduction of the descriptive content in introductory chemistry courses.
On the other hand, the courses experienced a closer relationship with physics concepts.
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