A. H. Johnstone

TEACHING OF CHEMISTRY - LOGICAL OR PSYCHOLOGICAL?

Chemistry is regarded as a difficult subject for students. The difficulties may lie in human learning as well as in the intrinsic nature of the subject. Concepts form from our senses by noticing common factors and regularities and by establishing examples and non-examples. This direct concept formation is possible in recognising, for instance, metals or flammable substances, but quite impossible for concepts like ‘element’ or ‘compound’, bonding types, internal crystal structures and family groupings such as alcohols, ketones or carbohydrates. The psychology for the formation of most of chemical concepts is quite different from that of the ‘normal’ world. We have the added complication of operating on and interrelating three levels of thought: the macro and tangible, the sub micro atomic and molecular, and the representational use of symbols and mathematics. It is psychological folly to introduce learners to ideas at all three levels simultaneously. Herein lies the origins of many misconceptions. The trained chemist can keep these three in balance, but not the learner. This paper explores the possibilities, for the curriculum, of a psychological approach in terms of curricular order, the gradual development of concepts, the function of laboratory work and the place of quantitative ideas. Chemical education research has advanced enough to offer pointers to the teacher, the administrator and the publisher of how our subject may be more effectively shared with our students. [Chem. Educ. Res. Pract. Eur.: 2000, 1, 9- 15]

Isolating topics of high perceived difficulty school biology

Abstract A technique devised to isolate topics of high perceived difficulty in a school biology syllabus is described. Results obtained from questioning school pupils, teachers, and university students indicate a large measure of agreement.

Investigation of students' cognitive structure in elementary genetics through word association tests

The word association test is one of the commonest and oldest educational tools for investigating the cognitive structure of learners. In this present study, a word association test was used to map the cognitive structure of areas of elementary genetics in first-year biology students. In order to map the structures, relatedness coefficient values and response frequencies were used. The results showed that the students generated many ideas related to given key words. However, they did not appear to see the overall picture as a network of related ideas. Implications for using the word association test in the classroom are discussed.

Room for scientific thought

Simultaneous studies of the effect of working memory space and field‐dependence on science performance at secondary and tertiary levels give insight into the way that students process new information. The idea of potential and usable processing space is explored and consequent teaching strategies are discussed.

Chemical education research in Glasgow in perspective

This paper describes the work of a large science education group (80+ workers) which, from 1969, has been tackling teaching and learning problems over a broad front. For much of the time, the group has worked within a Faculty of Science and has tried to take a scientific approach to the research. This approach is still followed although the Centre is now in a Faculty of Education. At the start, time was spent in gathering facts, looking for common factors, raising and testing hypotheses, generating working models and applying findings to real teaching and learning situations. This paper seeks to present an overview of the work up to about 1997, with illustrations from later work. Although the research applies to all science subjects, the emphasis here is on chemistry. The other papers in this issue exemplify the ongoing research which has arisen from this basic ground-laying and which has spread worldwide. [Chem. Educ. Res. Pract., 2006, 7 (2), 49-63]

A LANGUAGE PROBLEM REVISITED

A study of twenty years ago showed the extent of the problems associated with the misunderstanding of common language used in a science context. This present sample study indicates that the problems have not gone away. It also reveals that the problems are even greater for pupils whose second language is English. The study goes on to explore the underlying psychological problems caused by language blockages and attempts to measure their effects. The findings are, that pupils, struggling to learn science in a second language, lose at least 20% of their capacity to reason and understand in the process. This has a serious message for countries which, for otherwise good reasons, teach their pupils through the medium of English rather than in the native language. This message also applies to those who have to teach mixed language groups. [Chem. Educ. Res. Pract. Eur.: 2001, 2, 19-29]

Misconceptions in school thermodynamics

Based on the results of an investigation of the conceptual difficulties experienced by pupils studying the topic of chemical equilibrium for the Scottish Certificate of Education in higher grade chemistry and for the Certificate of Sixth-Year Studies. The approach to chemical equilibrium at higher grade is based on the concept of equal and opposite rates of reaction while at CSYS level a thermodynamics approach based on the concept of Gibbs free energy is employed. Conceptual difficulties experienced by pupils (and perhaps by teachers) with respect to the thermodynamics approach are discussed.

Understanding learning difficulties—A predictive research model

ABSTRACT This paper arises from investigations of the topics in science which students perceive to be difficult. An information processing model is described which relates student performance to the amount of information to be processed in a learning or problem-solving situation. When the student working memory capacity is exceeded, there is a sharp drop in performance, but some students (〈/i>10%) continue to operate efficiently with problems which exceed their capacity; they are probably employing chunking devices that enable them to reduce the problem demand to less than their limit of capacity. Empirical measurements give support to the model and suggest hypotheses for future research.

Learning Difficulties in School Science‐‐Towards a Working Hypothesis

Summaries English In an attempt to explain success and failure in problem‐solving by science students, the authors suggest that problem‐solving ability is associated with students’ ability to organize or ‘chunk’ the information provided in a problem into memorizable patterns. In line with general psychological findings, a short‐term memory capacity of 7 ± 2 chunks is accepted. If the short‐term memory is overloaded with too many pieces of information, the processing of this information (and, hence, effective problem‐solving) cannot take place unless such information can be effectively chunked. This hypothesis, which is derived from research studies, is exemplified by reference to chemical problems and its educational implications are discussed.

Concept mapping in problem based learning: a cautionary tale

Problem Based Learning (PBL) and Concept Mapping (CM) have parallel purposes, both based on a constructivist view of learning. In a Faculty of Medicine, PBL and CM have been applied together as the main learning modes. This provided an opportunity to test several hypotheses about the interaction of CM and PBL. Among them were: (i) Students using CMs for their study and revision would perform better on their assessment tasks, than those who did not. This was supported, but not strongly. (ii) Students with ‘good’ maps would do better than those with ‘poor’ maps. This was not supported. Many students with apparently ‘poor’ maps treated them as a sufficient set of keys to unlock very large databases and these students did well. Other students with ‘poor’ maps confessed to having a tenuous grip on their work and this accounted for the quality of their maps. This raises problems about using maps for assessment purposes. It may be that maps should be treated as very personal learning tools for the writer’s eyes only, analogous to a personal diary which could be easily misunderstood by a reader. [Chem. Educ. Res. Pract., 2006, 7 (2), 84-95]