This paper reports on a pedagogical approach to the teaching of chemical equations introduced to first year university students with little previous chemical knowledge. During the instruction period students had to interpret and construct diagrams of reactions at the submicro level, and relate them to chemical equations at the symbolic level with the aim of improving their conceptual understanding of chemical equations and stoichiometry. Students received instruction in symbol conventions, practice through graded tutorial tasks, and feedback on their efforts over the semester. Analysis of the student responses to formative test and summative exam items over consecutive years indicates that there was a consistent improvement in the abilities of the various cohorts to answer stoichiometry questions correctly. The responses provide evidence for diagrams of the submicro level being used as tools for reasoning in solving chemical problems, to recognise misconceptions of chemical formulae and to recognise the value of using various multiple representations of chemical reactions connecting the submicro and symbolic levels of representation. The student-generated submicro diagrams serve as a visualisation tool for teaching and learning abstract concepts in solving stoichiometric problems. We argue that the use of diagrams of the submicro level provides a more complete picture of the reaction, rather than a net summary of a chemical equation, leading to a deeper conceptual understanding.

Almost 700 Swedish and South African students from the upper secondary school and first-term chemistry university level responded to our survey on concepts of chemical bonding. The national secondary school curricula and most common textbooks for both countries were also surveyed and compared for their content on chemical bonding. Notable differences between the countries were found in textbooks and in the curriculum regarding the topics of ionic bonding, bond energetics and use of the VSEPR model, the latter being absent in the Swedish curriculum and ionic bonding not explicitly mentioned in the South African curriculum. To some extent these differences are reflected in the students’ responses to the survey. It is also clear that university teachers in both countries must prepare effective counter-measures against deep rooted misunderstandings. For the upper secondary school level it is suggested that the bond energetics and exothermic and endothermic reactions be clearly and carefully presented and separated as the study indicates that mixing of these two concepts is a major cause of confusion.

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Several studies have emphasised the importance of addressing social and emotional factors in facilitating adjustment to tertiary education. This article describes the Skills for Success in Science programme at the University of Cape Town. The broad aims were life skills development and improved adjustment which are assumed to underpin academic performance. Weekly small group sessions were held which addressed several areas, namely adjustment, group work and cooperative learning, coping and stress management, resources on campus, assertiveness and communications, time management, study skills and examination competence. The intervention was experiential and participative, and while not compulsory, attendance was very good. Evaluation via self-report questionnaires using standardised psychological scales as well as focus groups provided positive feedback from students who described it as a 'must' for all first year science students. The article supports the notion that student development should be located within their daily experience at universities.

Teaching organic chemistry at the undergraduate level has long been regarded as challenging and students are often alienated by the mass of detail which seems to characterise the subject. In this paper we investigate the practice of an accomplished lecturer by trying to capture and portray his pedagogical content knowledge, PCK, in order to reveal his tacit knowledge as a resource for others. Data analysed from interviews and a set of five introductory lectures showed the framing of Big Ideas designed to underpin later work in the course. Five manifestations of his practice emerged strongly from the data analysis, namely Explanations, Representations, Interaction with Students, Curricular Saliency and Topic Specific Strategies. This realisation allowed us to make inferences about his underlying knowledge and beliefs regarding how the discipline should be taught. We found that the most important aspect of his practice was his recognition of the basic underlying concepts to be mastered before starting the main part of the course, and his strong beliefs related to the learning of the discipline. The extraction and portrayal of these practices are a valuable resource for novice lecturers.

The development of the Chemistry Competence Test was prompted by the extensive curriculum changes in the South African school system after democracy was established in 1994. As chemists, we were concerned that there might be a lack of articulation between secondary and tertiary levels, since we anticipated that curriculum changes would have an impact on the knowledge base and skills development of prospective students. A diagnostic test developed initially to document proficiencies of first-time entering students to South African universities has proved to be a versatile instrument for multiple uses. Apart from monitoring levels of preparedness for tertiary chemistry during a period of systemic change, it has also been used to evaluate institutional placement policies, to identify specific conceptual problems and procedural deficiencies, and to measure conceptual gains over the course of the first year at university. In addition, its application for the prediction of risk of failure in first-year chemistry based on cognitive and non-cognitive variables was demonstrated. All these findings are valuable resources to inform lecturers who are concerned about minimizing the conceptual gap between secondary and tertiary chemistry.

Research has shown that a high level of content knowledge (CK) is necessary but not sufficient to develop the special knowledge base of expert teachers known as pedagogical content knowledge (PCK). This study contributes towards research to quantify the relationship between CK and PCK in science. In order to determine the proportion of the variance in PCK accounted for by the variance in CK, instruments are required which are valid and reliable as well as being unidimensional to measure person abilities for CK andPCK. An instrument consisting of two paper-and-pencil tests was designed to assess Grade 12 teachers' CK and PCK in organic chemistry. We used the Rasch measurement model to convert raw score data into interval measures and to provide empirical evidence for the validity, reliability and unidimensionality of the tests. The correlation between CK and PCK was estimated as r = .66 (p < .001). We found evidence to suggest that while topic-specific PCK (TSPCK) develops with increasing teaching experience, high levels of CK can be acquired with limited teaching experience. These findings support the hypothesis that CK is a requirement for the development of TSPCK; proficiency in CK is, however, not necessarily associated with high levels of TSPCK.