OpenUCT :: Browsing by Author "Davidowitz, Bette"

Browsing by Author "Davidowitz, Bette"

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Assessment of preparedness of first-year chemistry students: development and application of an instrument for diagnostic and placement purposes
(Southern African Association for Research in Mathematics, Science and Technology Education, 2008) Potgieter, Marietjie; Davidowitz, Bette; Venter, Elsie
Many universities in South Africa use alternative admissions tests together with results of the Grade 12 examinations for access of placement. These tests focus on academic literacy and mathematical skills and do not provide information about proficiencies in disciplines other than mathematics. The implementation of new curriculum for Grades 10-12 in South Africa generates a need to monitor preparedness of first-year students to align first-year curricula as closely as possible to the content of the new syllabi. The need for a tailor-made instrument to assess preparedness for chemistry at the tertiary level was prompted by the lack of suitable tests with the appropriate focus, depth and coverage for application in the South African context. This paper describes the development and evaluation of a test instrument designed to assess and monitor baseline conceptual understanding in chemistry at the secondary-tertiary interface. The study was carried out with mainstream students at the university of Pretoria and Cape Town (N=513 and 258, respectively). Data analysed using the Rasch measurement model confirmed that the majority of students from both cohorts was reasonably well prepared for chemistry at the tertiary level. The use of the instrument for diagnostic purpose was demonstrated. It was possible to identify gaps in the assumed pre-knowledge of students who have qualified for admission to chemistry at a tertiary level at their respective institutions. Inadequate pre-knowledge was most noticeable in the areas of chemical reactions and electrochemistry. In addition, the instrument also shows promise as a placement tool within programmes. Its predictive ability compares well with non-South African placement tests and with Grade 12 mathematics performance, the latter is widely used for this purpose in South Africa.
Open Access
Characterising learning in a demonstrator community serving first-year chemistry students at a South African university
(2010) Wallace, P Karen; Davidowitz, Bette; Rollnick, Marissa
Teaching assistants (or demonstrators as they are called at South African universities) have become indispensable to the delivery of teaching particularly to first-year students, due mainly to the growing need in tertiary institutions to balance increasing student numbers and needs with pressure on academic staff time and institutional resources. At most universities the role of teaching assistants falls to postgraduate students who are being trained in disciplinary research. In addition to funding their own studies, their participation in teaching activities is increasingly being recognised as preparation for possible careers in tertiary teaching. This study explored learning in a community of demonstrators in the first-year laboratories of a chemistry department at a South African university.
Open Access
Development and validation of instruments to assess content knowledge and topic specific pedagogical content knowledge of teachers of organic chemistry
(2013) Vokwana, Nonkanyiso Queen; Davidowitz, Bette
In 1986, Shulman described Pedagogical Content Knowledge (PCK), as the transformation of Content Knowledge into various forms which help students to understand the concepts. In a later study, Shulman (1987) identified the construct of PCK as one of the knowledge bases of teachers. Many researchers have proposed models to characterise this transformation of Content Knowledge (CK), one of the most recent of which describes the construct of Topic Specific PCK (TSPCK) (Mavhunga, 2012). This study attempts to evaluate the extent to which teachers of organic chemistry are able to transform their CK to TSPCK. The introduction of the National Curriculum Statement in South Africa in 2006 led to changes in the curriculum for all subjects; in particular there was an increase in emphasis on organic chemistry at Grade 12 level. The current research forms part of a larger project to investigate how teachers' knowledge of their subject matter affects the way they teach across several different contexts. It is premised on the assumption that PCK develops with experience and results from the transformation of CK. Two instruments based on the Mavhunga (2012) model were designed to assess Grade 12 teachers' TSPCK in organic chemistry. Her model proposes that topic specific PCK results from the transformation of CK; thus Content Knowledge is considered to be a prerequisite to develop TSPCK. Thus two instruments are required, one each to evaluate CK and TSPCK. A pilot study was conducted with a small group of teachers and the findings were used to refine the instruments. Expert teachers at local schools were consulted and assisted in the development process of the instruments, the final versions of which were administered to a larger cohort of 44 science teachers from diverse schools. The CK instrument was assessed as a conventional test on organic chemistry while the TSPCK instrument was scored using a specially designed rubric. The research methodology used a mixed methods approach to transform data collected into numerical clusters as well as to carry out a qualitative analysis. The data was analysed to yield raw scores which were later subjected to Rasch analysis. This measurement model was used to validate the instruments and also to convert raw scores into interval data. According to the Rasch analysis, both instruments met the criteria of validity and internal consistency. The findings from the CK instrument revealed that the majority of teachers performed well. Teachers with university training achieved higher scores than those trained at technikons and colleges. Performance on the TSPCK instrument was not as strong as for CK; teachers with little experience revealed less complete levels of TSPCK than those with more experience. A reasonable correlation between levels of CK and TSPCK was confirmed by a value of r = 0.68 (p< .0005) for the correlation coefficient derived from a scatter plot of CK versus TSPCK. This implies that an estimated 46% of the variance in TSPCK is accounted for by the variance in CK and provides evidence for the assumption that CK is a prerequisite for TSPCK. The main findings from this project revealed that low levels of CK are likely to result in lower levels of TSPCK while high levels of CK are likely to result in high levels of TSPCK. On the other hand the study also revealed that high levels of CK do not necessarily translate into high levels of TSPCK. An unanticipated outcome of the study was that in some cases, lower than average levels of CK can translate into high levels of TSPCK. The Rasch analysis also enabled the refinement of the CK instrument and the rubric developed to score the TSPCK instrument. The refinements will allow the researchers to use the valuable data collected during the course of this particular study as part of a data set for any future study. The instruments developed for this study have the potential to be used for a large-scale implementation to obtain a more nuanced picture of the level of PCK in organic chemistry in the teaching cohort in South Africa.
Open Access
Facilitating adjustment to higher education: towards enhancing academic functioning in an academic development programme
(Unisa Press, 2008) Davidowitz, Bette; Schreiber, Birgit
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 co-operative 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.
Open Access
Grade 12 Achievement Rating Scales in the New National Senior Certificate as Indication of Preparedness for Tertiary Chemistry
(2010) Potgieter, Marietjie; Davidowitz, Bette
There has been much discussion on the impact of the new curricula for Grades 10–12 on the preparedness for tertiary studies of the 2009 cohort in subjects such as mathematics, chemistry and physics. Using the Chemical Competence Test that was developed and refined earlier, we have evaluated the proficiencies of incoming students to determine the shifts in preparedness for tertiary chemistry that occurred after students wrote the National Senior Certificate (NSC) in South Africa for the first time in 2008. Data were collected in 2009 for first-time entering students at the Universities of Pretoria (UP) (N = 828) and Cape Town (UCT) (N = 315) and compared with that of students who were educated according to the former National Education curriculum (NATED 550) (2005: NUP+UCT = 776). The raw score results showed a decline in proficiency in all topics, and significantly reduced skills development, with mastery of acids and bases showing the most serious decline. Rasch analysis of the data indicated that a 12 percentage point shift in preparedness occurred in 2009 compared with 2005. The contribution to this shift of a mismatch between the new NSC rating scale and the one used previously was also investigated. The implications of the findings for selection and placement and teaching of first year chemistry courses are discussed.
Open Access
Improving performance in a second year chemistry course: An evaluation of a tutorial scheme on the learning of chemistry
(2005) Davidowitz, Bette; Rollnick, Marissa
Throughput of students is a concern for academic departments especially since it will be the basis of a new funding formula for tertiary institutions. In order to reduce content for increased mastery, and ensure student engagement with chemical concepts, tutorials were introduced for two of the second year chemistry sub-disciplines at UCT in the place of some formal lectures. The impact of this innovation was investigated using questionnaires, interviews and a study of opportunistic data such as examination results. Analysis of the data showed that the overall pass rate increased noticeably as did the number of students achieving high marks. Student, tutor and lecturer feedback lent credence to the belief that the improvement was largely due to the introduction of the tutorial scheme. In addition, some noteworthy differences between the sub-disciplines were identified. Some of these differences were attributed to the lecturer’s understanding of his own teaching.
Open Access
Increasing the signal to noise ratio in a chemistry laboratory. Improving a practical for academic development students
(2003) Davidowitz, Bette; Rollnick, Marissa; Fakudze, Cynthia
In practical sessions students lack sufficient time or opportunity for deep processing of information. If the signal to noise ratio is too low, it can obscure the ‘chemical message’ which the lecturer is trying to convey. This study reports on an action research driven attempt to improve on a Hess’s Law experiment, well known in most first year curricula. Data collected in 2000 indicated that students struggled primarily because there were too many practical demands to allow them to focus on the concepts involved. The exercise was thus divided into two sessions in 2001, the first to address the issues related to techniques required, the second, similar to the experiment in 2000. Analysis of data collected in 2001 shows that the changes made a significant impact on the effectiveness of the laboratory session.
Metadata only
Preparedness for tertiary chemistry: issues of placement and performance of academic development programmes
(Unisa Press, 2008) Davidowitz, Bette; Potgieter, Marietjie; Mathabatha, S. S.
The introduction of an outcomes-based curriculum in South Africa together with a new syllabus for physical sciences for grades 10-12, prompted the development of an instrument to monitor conceptual understanding in chemistry at the secondary-tertiary interface. This instrument was used to evaluate placement within different programmes at tertiary institutions as well as improvement in the conceptual understanding of chemistry during the first year of instruction. Comparison of preparedness revealed distinct profiles for proficiencies of mainstream and academic development cohorts, respectively, at the Universities of Cape Town, UCT, and Pretoria, UP, but not at the University of Limpopo, UL, which raises doubts about the placement of students at that institution. Unnecessary duplication of offerings for under-prepared students was found at UP. The academic development programmes at UCT and UP were effective in raising the level of conceptual understanding of students while students in the UL programme showed very little improvement.
Open Access
Preparedness for tertiary chemistry: multiple applications of the chemistry competence test for diagnostic and prediction purposes
(The Royal Society of Chemistry, 2011) Davidowitz, Bette; Potgieter, Marietjie
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.
Open Access
Reactivity studies of phosphoric amides and esters
(1984) Davidowitz, Bette; Modro, Tomasz A
The effect of protonation and Lewis acid-base interaction on the ¹H n.m.r. chemical shifts of the ester and amide bonds in selected phosphoramidates (RO)₂P(O)NR'₂ was investigated. The results are interpreted in terms of the interaction of the phosphoryl oxygen atom with Lewis acids and oxygen/nitrogen diprotonation in trifluoromethanesulphonic acid. Intramolecular nucleophilic displacement of the halide ion from secondary β-chloroethyl-substituted phosphoramidates X₂P(O)NHCH₂CH₂Cl, diamidates (RO) (MeNH)P(O)NHCH₂CH₂Cl and β-chloroethyl phosphates Y(MeO)P(O)OCH₂CH₂Cl, was studied under conditions of electrophilic (Ag+) and basic (NaH) catalysis. 1,3-Substitution by the nitrogen atom of the phosphdramidates, yielding ethylenimine derivatives was found to be the preferred reaction-pathway; the alternative 1,5-reaction involving the amide nittogen or phosphoryl oxygen atoms was not observed. No intramolecular nucleophilic displacement occurred in the β-chloroethyl phosphate esters.
Open Access
Stakeholder perceptions of the efficacy of a capstone course introduced to assist accounting students in developing pervasive skills
(2016) Maughan, Paul; Davidowitz, Bette
A capstone course, Business Analysis and Governance (BAG), compulsory for all students studying towards becoming chartered accountants, was introduced at the University of Cape Town (UCT) in 2012. It was designed to develop pervasive skills in response to the competency framework that was developed in 2008 by the South African Institute of Chartered Accountants (SAICA), the professional accounting body. This study explored whether or not the capstone course has assisted in developing the pervasive skills of students. The effectiveness of specific interventions namely a Mergers and Acquisitions (M&A) project, the inclusion of current business research area questions in assessments as well as company analysis was also investigated. Research was conducted in the critical theory tradition, in particular following the work done by the prominent psychologist, Kurt Lewin who is considered as one of the founders of social psychology. He is also often credited as being pivotal to the emergence of Action Research which was used in this research project. Action Research required an annual cycle of observation, action, reflection and planning over the initial four year period of the capstone course.
Open Access
Students learning-approach profiles in relation to their university experience and success
(Taylor & Francis, 2008) Rollnick, Marissa; Davidowitz, Bette; Keane, Moyra; Bapoo, Abdool; Magadla, Lizo
What is the connection between student success and their approaches to learning? Do learning approaches develop with university experience? We explored these questions by constructing profiles using a specially developed fixed response instrument and administering this to students at two similar South African universities. Groups consisted of access course applicants, access course students, and first and second year mainstream chemistry students. Successful senior students showed more sophisticated approaches to learning than other groups. Unsuccessful students fell into two different categories: those using a surface approach, and predominantly first generation tertiary students who used deep approaches. We discuss possible reasons for the latter group's lack of success. These findings raise questions for academic development practitioners advocating the use of deep approaches. The instrument was found to be useful for both diagnostic and pedagogic purposes.
Open Access
Studies directed towards the synthesis of metal-containing ketones
(1977) Davidowitz, Bette; Cragg, G M L; Haines, Raymond J
The photochemistry of organometallic compounds is receiving increasing attention in the current literature, but as yet, little work has been reported on the photochemistry of metal-containing ketones. The objective of the work reported in this thesis was the synthesis of ligands for the formation of suitable metal-containing ketones. The initial studies were directed at the preparation of β- and ϒ-hydroxyketones by a variety of methods, but the major effort was later concentrated on the synthesis of phosphorus derivatives of o-hydroxyphenyl alkyl ketones . The reaction of o-hydroxyphenyl alkyl ketones with phosphorus trichloride afforded 2-chloro- 1,3,2-dioxaphosphorinans which were readily converted to the corresponding 2-alkoxy derivatives by reaction with various alcohols. Extension of the study to acteylacetone indicated that an analogous reaction occurs to give highly labile products. This part of the work has been accepted for publication in Chemical Communications. The reaction of o-hydroxyphenyl alkyl ketones with other phosphorus halides, such as dichlorophenyl phosphine and chlorodiphenylphosphine, has also been investigated. Reaction of the former reagent with o-hydroxyacetophenone gave a crystalline phosphorus-containing derivative; spectroscopic evidence indicates that this compound possesses an unusual structure and it is currently being studied by X-ray crystallography.
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Use of the Rasch measurement model to explore the relationship between content knowledge and topic-specific pedagogical content knowledge for organic chemistry
(Taylor & Francis, 2016-06) Davidowitz, Bette; Potgieter, Marietjie
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 and PCK. 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. [Editor's note: this post-print has been embargoed until January 2018]
Open Access
What lies at the heart of good undergraduate teaching? A case study in organic chemistry
(The Royal Society of Chemistry, 2011) Davidowitz, Bette; Rollnick, Marissa
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.

Browsing by Author "Davidowitz, Bette"

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