Thesis (M.Med.Sc.)--University of Hong Kong, 2003. / Also available in print.

Thesis (Ph. D.)--Open University. BLDSC no. DX184567.

A journey into the past century of genetics history reveals transformations of the concept of the gene through notions of discrete units that obeyed Mendelian laws to the modem bewildering gene concept. We can no longer say that a gene is a sequence of DNA that continuously and uniquely codes for a particular protein - it is the phenotype that defines the gene, rather than the other way around. Research into learning in genetics has largely focussed on issues such as problem solving and the process of meiosis. The central concept of the gene, however, has had little attention. How do students learn about the concept of the gene during an introductory high school genetics course? Is it possible to justify an analogy between the historical development of the concept of the gene and student learning? Can student learning about the gene be described as conceptual change and what are the factors that might influence this process? These are the issues that are addressed in this thesis.The general purpose of this study was to investigate Year 10 students' learning about the concept of the gene. The theoretical framework is embedded in the personal and social paradigms of constructivism and a multidimensional interpretive framework for conceptual change was utilised, enabling the data to be interpreted from ontological, epistemological and social/affective perspectives.A total of eight classroom sites were used to collect data as a series of linked case studies. Data from three of these cases were used to investigate Year 10 student learning about the concept of the gene and one of the cases was used to make an in-depth examination of individual student learning and conceptual change. The larger series of eight cases was drawn upon to provide data to support assertions made about the factors influencing conceptual change. Methods of data collection included classroom ++ / observations, student interviews, teacher interviews, student work-sheets and classroom quizzes. Traditional notions of research rigour were side-stepped for different standards that better suit the paradigm of naturalistic or constructivist inquiry. Credibility, transferability, dependability and confirmability were enhanced by a thorough system of triangulation at the data source and collection level and at the data interpretation level for each of the research questions. Theory triangulation also was utilised through the multidimensional framework for conceptual change. In addition, methodology and case studies with a thick description that allow the readers to proceed on their own tracking and interpretation process are provided.The results of the research reported in this thesis are examined from several different perspectives. From an ontological perspective, Year 10 student learning about the concept of the gene is described by a proposed learning pathway that consists of four ontologically distinct models. The majority of the students in the classes, however, did not progress the entire length of the pathway, rather they completed their introductory genetics course with an "active particle gene" conception. This is the second model in the pathway. In other words, few students were found to have a modern conception of the gene.From an epistemological perspective of conceptual change, six students' post instruction conceptions of genes were classified as being intelligible, plausible or fruitful to the learner. For example, at the end of the genetics course, Alastair had an active particle gene" conception that he viewed as intelligible and plausible and Douglas had a "productive sequence of instructions gene" conception that was intelligible, plausible and fruitful. The student learning investigated in this study was described as conceptual change of the ++ / weaker kind that proceeded in an evolutionary manner because the new conceptions involved detailed explanations of the gene concept and were reconciled with old conceptions.A social/affective perspective revealed information about how the teaching approach and student interest in genetics influenced the process of conceptual change. Lack of student interest in submicroscopic explanatory phenomena and algorithmic approaches to problem solving were found to inhibit learning about the gene concept. The nature of the content was another perspective used to examine conceptual change. The process aspects of genetics content were said by teachers to be difficult to teach, and students found it difficult to link together ideas taught in genetics such as the double helix structure of DNA, the genetic code, protein synthesis and phenotypic expression. The different levels of representation in genetics content confused students; for example, Anna was unable to differentiate between submicroscopic DNA structure and symbolic representations of the genetic code such as the letters A, T, C and G.Implications from the study are that for students to construct a better understanding of the concept of the gene, teachers and curriculum writers should use the gene as a central organising concept in genetics courses and explicitly encourage students to build links with other genetics concepts. Improvements need to be made in the way that teachers teach genetics processes so that students are actively involved in thinking about the processes, especially by making the connections between the structure and function of genes. In addition, students need to be involved in learning strategies that will help to raise the status of sophisticated models of genes in their cognitive structures.Having the multidimensional framework for conceptual change as the interpretive framework and utilising ++ / different perspectives of conceptual change enabled triangulation of the theoretical interpretations of the data. This can be likened to creating a three dimensional picture of a learning situation rather than the equivalent of a linear, or two dimensional representation of a complex three dimensional phenomenon. A major implication for conceptual change research from this study is that the multidimensional framework has the potential to enable researchers and teachers to better understand the process of conceptual change in many fields. The thesis concludes with a discussion of the limitations of the study and future directions for research.

This study analyses the effect of introducing student portfolios as a means of assessing the learning of mathematics. It examines the intended and the unforeseen outcomes in terms of the students, the caregivers, and the teachers involved, using quantitative data to match classroom environments with the response to the innovation. A major focus of the qualitative aspect of the study is the decisionmaking process that was associated with the implementation of change. For this study, all the junior students in a New Zealand secondary school were asked to compile portfolios of their mathematical work. The portfolios were graded by the teachers, the marks contributing to the students' assessments for the year's work. At the outset, the plan was to survey the 510 students involved to determine their attitude towards mathematics, survey them again once the innovation was in place to quantify the classroom environment, then repeat the first survey. Analysis was expected to reveal whether classroom environments that approximated a "portfolio culture" (Duschl & Gitomer, 1991) contributed to an improved attitude towards mathematics. This quantitative approach was supplemented with taped interviews of students and teachers, ongoing records of less formal interactions, review of examination marks and school reports, and questionnaires mailed to the homes of a sample of the students. As the study progressed, it emerged that the major impact was on the teachers, and the focus shifted to them. For four years, follow-up surveys were conducted with teachers, including those who had transferred to other schools. The study found that all students can benefit from portfolios, both in terms of skills and attitude towards mathematics. / Portfolios legitimated the involvement of caregivers, a positive change that provided greater links between classroom activity and the world of employment. The professional practice of teachers was affected by portfolios, prompting development of new classroom resources and techniques, increased collegial cooperation, and well-informed reflection on teaching and assessment. Teachers maintain great influence on classroom culture, and for many of those involved in the study, portfolios prompted a renewed interest in the process undertaken by students as they develop mathematical ideas, and a change in the relationship between teacher and students. The "portfolio culture" resulted in students improving in their appreciation of mathematics, and a changed role for the student within the social environment of the classroom.

For urban secondary students, the benefits of attending after-school programs may not be solely academic—rather, their attendance and participation may yield more fundamental development needs. A supportive network of influential and positive mentors can improve urban secondary students learning experience outside of the classroom. Urban secondary students may have access to support and assistance from mentors by attending an after-school program. This qualitative ethnographic study explored the perceptions of tutors working in an after-school program in a large urban school district. This study attempted to understand of the tutors’ motivation for working with students, the support that they provided to the students, and the needs they thought the students have. The data was collected through individual interviews and observations of the tutors during the program. Data was analyzed for common themes to support the research questions. From the interview questions, a total of twelve themes were generated to answer the three research questions. According to the participants interviewed in this study, the interactions with the tutors in the program served as catalysts that promoted student academic success and social development. While the themes originating from the questioned varied, the underlying conclusion of the interview data from this research study is that students take more of an interest in themselves and their academic ability when someone else takes a genuine interest in them and their academic ability.

Research has indicated that adolescents hold both negative and positive attitudes and have common misconceptions about breastfeeding that appear to result from their limited knowledge and reduced exposure to breastfeeding. The purpose of this study was to determine the knowledge and attitudes toward breastfeeding of adolescent male and female secondary school students. The study also sought to elicit information on factors that may influence the decision regarding future infant feeding methods. Self-efficacy theory was the theoretical framework to guide the study. This quantitative descriptive study, using a cross-sectional design, involved consenting secondary school students' completing a self-report questionnaire. The study employed purposive sampling and included 1845 males and females in both year-nine and year-12 at designated metropolitan and rural secondary schools in 2001. Analyses of the data were performed using the Statistical Package for Social Science (version 10.7). Statistical procedures involved chi-square analysis, Student's independent t-test and univariate analysis of variance. Spearman's rank order correlation coefficient was used to describe the relationship between the secondary school student respondents' knowledge of and their attitudes toward breastfeeding. The study results indicate that overall Western Australian adolescent secondary school students have less than ideal knowledge of breastfeeding which is consistent with findings from other studies. Higher breastfeeding knowledge scores were reported in year-12 for both male and female students. For both year groups, female students had higher breastfeeding knowledge scores than male students. With regards to attitudes toward breastfeeding, students had a tendency for neutral responses to attitude questions. / However, overall and for both year groups, female students were found to be more positive towards breastfeeding than male students. The comparison of rural to metropolitan students found that metropolitan students had higher breastfeeding knowledge and were more positive towards breastfeeding than rural students. The metropolitan students were also more inclined to consider breastfeeding future children than rural students. Consideration of breastfeeding future children was similar for both male and female students. Comparison of the combination of gender, year and site revealed higher breastfeeding knowledge and more positive attitudes to breastfeeding in both rural and metropolitan female year-12 respondents. Sources of efficacy information, particularly persuasion/education, were more prominent in female secondary school respondents than male secondary school respondents when considering factors influencing adolescent attitudes toward breastfeeding. The adolescent's acceptance of gender identity could be argued as a reason for the more positive breastfeeding attitudes in female respondents. Students who were breastfed or exposed to breastfeeding either through role models (ie mothers), reading about breastfeeding, media or family influence had greater knowledge and were more positive towards breastfeeding. This study suggests that breastfeeding and lactation information needs to be addressed in the early years of development in order to increase breastfeeding knowledge and promote positive attitudes. Information pertinent to the health benefits of breastfeeding needs to be included in health and nutrition education and addressed through targeted education programs. / Education and health promotion activities could be guided using the four sources of efficacy information in relation to the benefits of breastfeeding. Opportunities for the role modelling of positive breastfeeding attitudes, and consistent support from the school-based health professionals may assist to reduce the adolescent student's unmet informational needs in relation to breastfeeding. A recommendation from this study is the provision of lactation and breastfeeding education for community-based high school nurses as these health professionals are a key element in health education and health promotion in the school setting.

The teaching of literature in New South Wales secondary schools has shifted significantly in the period 1990-2001, influenced both by the newer literary theories and by the belated application to the teaching of Shakespeare of active approaches designed to encourage students to think dramatically, think theatrically when approaching playscripts. This essay explores the way in which the author's research papers and the pedagogical materials that they have generated have supported and indeed to some extent been instrumental in bringing about these changes. Beginning with an overview of literature teaching in secondary schools 1990, the essay identifies the questions which have driven the research over the past decade: 1/. Can Reader-Response Theory be made explicit to junior and middle secondary students? Would such knowledge be of value to them? 2/. Are there other aspects of modern literary theory that are worth exploring with secondary students? 3/. Can young readers be encouraged to reflect on their processes of response? Is such an endeavour worthwhile? 4/. How can the teaching of Shakespeare be improved? The last question led the author, during the period of candidature, to explore the puzzling question of why the pedagogy of teaching Shakespeare had lagged so far behind the methods employed in the teaching of other literature, and thus to an historical enquiry covering the teaching of Shakespeare over the past hundred years. At the same time, the author has been concerned to refine some of his teaching methods in order to encourage senior students to explore the plays from, for example, feminist, new historicist and post-colonial perspectives. / Doctor of Education (Ed.D.)

This project looks at the ways in which masculine identities are constructed and perceived in secondary schools. It identifies some of the links between broader gender politics and the more specific area of masculinities as they apply to the lives of gay-identified and non-identified secondary school students. Through focussed discussion with groups of students the research describes types of behaviours that are characterised by students as desirable or undesirable and the perceived relationship of such behaviours with particular sexualities. In this thesis I interrogate the treatment (including bullying, harassment and lack of acknowledgment of the gay experience), in schools, of boys who express gender unorthodoxy/non-hegemonic masculinities. In order to understand this behaviour I look at the means of control of such expressions as exercised by other students and teachers and explore the motivation behind this control. Through listening to the stories of students I identify the need to evaluate school policy and pedagogical practices with a view to making the educational experience more inclusive of a broad range of masculinities and sexualities and therefore a more relevant, positive and productive one.

The primary purpose of this study was to develop a two-tier multiple choice diagnostic instrument to assess Singapore Grade 10 students' (15 to 17 years old) understanding and alternative conceptions of qualitative analysis. Additional and related purposes were to determine whether more advanced chemistry students, for example, junior college (Grade 11 and 12) students, undergraduates and graduate trainee-teachers have a better understanding of basic qualitative analysis than secondary students, and to develop appropriate teaching strategies and materials on qualitative analysis based on the findings of this study and a review of the literature on practical work.The results from the administration of the diagnostic instrument showed that Singapore Grade 10 students had many alternative conceptions related to qualitative analysis, and these were grouped under the headings of 'Displacement', 'Redox', 'Dissolution', 'Addition of acid' and 'Heating'. The cross-age study showed that the more advanced chemistry students generally had a better understanding of basic qualitative analysis but had similar alternative conceptions as the Grade 10 students. However, the alternative conceptions identified were consistently held by only a small number of students across all contexts examined in the diagnostic instrument, suggesting that a number of students either had more than one conception for a particular concept or no conceptions at all. The results from the trial of the qualitative analysis teaching package indicated that the teaching package was feasible. Teachers involved in the trial found it structured and comprehensive, and the students who experienced the teaching package performed better on the diagnostic instrument than a comparison group.The study recommends that better ways of conducting qualitative analysis practical work are required, and using the teaching ++ / package may be a step in this direction. The study also raises questions about the value of teaching qualitative analysis in secondary schools when important reactions involved in qualitative analysis are omitted from the syllabus, and when there is little incentive and time in the school curriculum for learners to understand what they are doing in qualitative analysis.

A quasi-longitudinal case study was used to determine the effects on secondary students of participation in a program of enrichment and extracurricular science activities in terms of their interest and enjoyment in being involved in science activities, their motivation to continue to participate in science, and their perceptions about scientists and about the role of science in society. Two groups of students in a school were followed simultaneously, a junior cohort through Years 8 to 10 and a senior cohort through Years 10 to 12. Both qualitative and quantitative data were collected from 20 students; five girls and five boys from each cohort. A strong positive relationship was found between changes in students' interest and enjoyment and changes in their motivation, and both these variables increased, in an overall sense for the combined student population, during the study period. All students generally held a high perception of both the normality of scientists and the importance of science in society throughout the study period. Participation in science activities impacted overall positively, but to varying extents for different activities, on all four dependent variables. Suggestions for the structure and/or conduct of competitions, excursions, and practical work, including the design of museum exhibits, and implications for further research are presented.