Guia Covid-19
Imprimir Republish

Education

Nothing is lost, everything is transformed

Teaching an updated history of science could be the best way to help students understand chemistry

078-081_Quimica_208-1Léo RamosAccording to the report Químicos BR: demandas e desafios para o século XXI (Brazilian Chemists: demands and challenges in the 21st century), published by the Brazilian Chemical Society (2012), the number of universities offering degrees in chemistry increased from 96 to 230 from 2000 and 2010. A remarkable detail is that, of these, 70% are undergraduate courses that offer a teaching certificate option. There will be a significant increase in the number of chemistry graduates in the coming years, but still unknown is if there will be enough of them to meet the demands of industry because the vast majority will go on to work as teachers and not in industry. In this case, one question remains: will they be effective teachers, able to train good professionals that fulfill the future technological needs of the country?

“There are concerns when analyzing educational demands in a growing economy with many expectations, as the most vulnerable period in the education of chemists is elementary and secondary school,” says Vanderlan Bolzani, of the Universidade Estadual Paulista Júlio de Mesquita Filho Institute of Chemistry in Araraquara (UNESP-IQ-Ar). “Another question that is now being asked throughout the country is if training in chemistry is now sufficient to satisfy the needs of Brazilian society. Is it preparing professionals to work in an innovative, multidisciplinary field?” questions the researcher.

“That will only happen when students understand the complexity of chemistry and, especially, its essential contribution to sustainable development, which has been greatly disseminated. Teachers need to understand that the goal is not only to teach content, but also to help these students understand what characteristics of scientific knowledge are significant enough to be included in the basic education of all students,” explains Paulo Alves Porto, of the University of São Paulo Institute of Chemistry. In his proposal entitled Explorando interfaces entre a história da ciência e o ensino da química (Exploring interfaces between the history of science and the teaching of chemistry), funded by FAPESP, he suggests that the path to achieve this is through the history of science.

According to Porto, analysis of the historical process behind the development of science can help give meaning to chemical knowledge, and help students understand the issues that motivated the proposal of concepts and the characteristic approach that chemists have towards reality. A survey of the image of chemistry in the twentieth and twenty-first centuries, and how this impacts teaching of the discipline, may be an interesting starting point.

Authors such as LaFollette, Lazlo, Kovac, Schummer, and others have noted that during the 1930s, with the rise in the consumption of new products, chemistry was pragmatically accepted by society. From 1950 to 2000, the postwar military context transformed chemists from the benefactors of mankind into the villains largely responsible for environmental degradation. Society also began to question the ethical issues, such as research on chemical weapons, chemical accidents, environmental pollution, and the negative (and unintentional) “side effects” of chemicals.

“Misinformation about chemistry by society in general shows that the education of chemists has to incorporate historical, philosophical and sociological analyses of scientific practices, as well as the rules that govern them. This would result in ethical reflections that, together with education, would become a part of chemistry practices and help society think about chemistry more clearly,” says the researcher. Porto also notes that the adoption of physics as the paradigmatic science led to a “subordinate status” for chemistry, with chemistry being viewed, erroneously, as having less correct theories, models and ways of thinking than those of physics.

However, he points out the difference between “practicing chemistry,” which follows its procedural rules, and “teaching chemistry,” where greater reflection is needed with respect to the various philosophical positions, introducing students to the controversies, showing the pros and cons of each aspect of the history of chemical science. A major obstacle, however, is the lack of publications available to specialists. “The history of science portrayed in teaching materials does not reflect the current state of the history of science and is based on outdated perspectives,” says Maria Helena Roxo Beltran, of the Graduate Studies Program in the History of Science at the Pontifical Catholic University of São Paulo (PUC-SP), where she is developing, at Cesima (the Simão Mathias Center for Research on the History of Science at PUC-SP), the study entitled História da ciência e ensino: abordagens interdisciplinares no ensino superior (The history of science and teaching: interdisciplinary approaches in higher education) (diagnostics, continuing education and specialized training for teachers), funded by Capes through the Education Observatory Program.

According to the researcher, most textbooks or books used in the classroom treat the history of science as the heroic saga of knowledge with “parents” of scientific ideas. The past is analyzed from the point of view of the present and the “good ideas” that resemble current ideas are selected to show continuity. Maria Helena Beltran recalls that the alchemy practices—many of which are still used today—are stressed, while alchemy’s symbolic explanations are set aside as erroneous dreams. Thus, alchemy is reduced to a “primitive chemistry” and not seen as legitimate knowledge, valued in its time.

At the other extreme would be a vision defined by the concept that ruptures or revolutions stimulated knowledge, as Thomas S. Kuhn claims. Current historiographical perspectives that suggest continuities and ruptures do not reach educators. According to Beltran, scientific debates from the past need to be brought into the classroom so students can analyze the internal consistency of the various theories proposed to investigate the same phenomenon. But, to do so, we need to prepare texts and instructional materials that focus on the history of science and the interfaces between the history of science and education, as well as specialist continuing education courses for teachers in these same areas. Beltran hopes that these initiatives, which are being developed as part of her project História da ciência e ensino: abordagens interdisciplinares no ensino superior, will contribute to the interdisciplinary training of teachers of all levels in the history of science.

A conceptual approach
In his project, Paulo Alves Porto found that textbooks do not effectively overcome historical and conceptual stereotypes and misconceptions. According to the researcher, scientists tend to appear as “figures working in an isolated manner because their intelligence is so far beyond that of a tiny portion of the population.” He also believes that the historical information in the textbooks he analyzed was “slight and superficial” and transformations tend to be described as having taken place in a linear and direct manner, as if “knowledge was being improved over time, without disputes or ruptures.” A single experiment is shown as able to “overturn” a theory, leading immediately to another, says Porto.

“Reports of contributions from a scientific community are few and far between. In general, a scientist is seen as able to do everything alone,” says the historian. An example is Thomson’s model that, according to the texts, “had” to be replaced by Rutherford’s. Textbooks, in general, do not mention that there were several other atomic models under discussion, including other “nuclear” models, prior to Rutherford’s. As a curiosity, the famous “plum pudding” analogy, so often repeated in books, is totally inadequate for representing Thomson’s model, since the model did not describe static electrons distributed randomly, but rather moving in concentric rings within the positive sphere.

078-081_Quimica_208-2Léo Ramos

As the teaching profession tends to be undervalued, noted the professor, professionals from other fields, who do not have teaching qualifications, may end up teaching, and the untrained teacher may have no idea why he is teaching certain content, nor the reason why a given book is chosen. Even teachers of chemistry courses do not always analyze the material they use: this is why textbooks end up becoming the most important course material in high school chemistry.

“In a way, the trajectory of textbooks in Brazil reflects how Brazilians think about chemistry,” said Porto. In the 1950s and 1960s, Americans changed the materials used to teach chemistry at the university level. The spirit of those books was to train more creative professionals, rather than those who could just reproduce results. They valued research, development and operations, emphasizing mathematics and physics with particular emphasis on problem solving. The post-war period made chemistry a “glamorous” field, promising jobs and national progress.

Chemistry as a means to an end
Along with the reduction of descriptive content in introductory courses came greater emphasis on physics concepts. Gradually, the American books used in Brazil became oriented towards the many students who did not see chemistry as an objective, but as a means to an engineering, medical or other degree. “On the other hand, some researchers in chemistry pedagogy deconstructed the classical division of the sub-areas of chemistry that are supposedly responsible for a ‘parochialism’ that would hinder the recognition of chemistry as a science of interfaces,” says the researcher. Books then returned to showing the relationship between chemistry and other areas of interest and the number of “everyday” examples increased.

Books have come to rely increasingly on the ability of students to follow a more rigorous approach. Many teachers, for example, have begun to reject books with greater emphasis on mathematical rigor. According to Porto, this history of changes in textbooks shows the multifaceted dialog between chemistry and the forces exerted by society in each era. “The history of science allows us to show that science involves debates and conflicts, as in any other area of human activity. But the construction and analysis of possible interfaces between the history of science and the teaching of chemistry is only possible through dialog between science historians and educators. This dialog is just beginning,” says Maria Helena Beltran, who invites us to the Fourth History of Science and Education Day, to be held July 4-6, 2013 (www.pucsp.br / jornadahcensino).

Project
Investigating the presence of the history of science in chemistry textbooks (nº 2007/02542-4); Grant Mechanism Regular Research Project Grant; Coordinator Paulo Alves Porto/USP; Investment R$19,202.88 (FAPESP).

Republish