The Framework for K-12 Science Education, the foundation for the Next Generation Science Standards, identifies scientific explanation as one of the eight practices "essential for learning science." In order to design professional development to help teachers implement these new standards, we need to assess students' current skill level in explanation construction, characterize current teacher practice surrounding it, and identify best practices for supporting students in explanation construction. This multiple-case study investigated teacher practice in eight high school science inquiry units in the Portland metro area and the scientific explanations the students produced in their work samples. Teacher Instructional Portfolios (TIPs) were analyzed with a TIP rubric based on best practices in teaching science inquiry and a qualitative coding scheme. Written scientific explanations were analyzed with an explanation rubric and qualitative codes. Relationships between instructional practices and explanation quality were examined. The study found that students struggle to produce high quality explanations. They have the most difficulty including adequate reasoning with science content. Also, teachers need to be familiar with the components of explanation and use a variety of pedagogical techniques to support students' explanation construction. Finally, the topic of the science inquiry activity should be strongly connected to the content in the unit, and students need a firm grasp of the scientific theory or model on which their research questions are based to adequately explain their inquiry results.

published_or_final_version / Statistics / Master / Master of Social Sciences

published_or_final_version / Education / Master / Master of Education

Recent studies on human cognition have presented credible evidence that learners are not tabula rasa as previously conceived by traditional theorists, rather they enter new lessons with some preconceptions, most of which are resistant to change in spite of teachers' efforts to assuage them. As such the challenges confronting science educators and educational psychologists are to understand the nature of learners' preconceptions, designing and implement appropriate instructional interventions that would enable the learners become aware of and reconcile their conceptions that are inconsistent with accepted views of science. Several perspectives have been advocated on how learners' preconceptions can be modified through instructions. While traditional theorists subscribe to substitution of inaccurate conceptions with accurate ones, the constructivists identify with giving the learners autonomy to inquire and re-evaluate their own ideas. The former has been confronted with widespread criticism and is becoming less and less tenable. This research identifies with the latter. Conceptual change entails restructuring of ideas. It is a cognitive process that involves change in attitude toward learning. Based on the theoretical assumption that learning is facilitated through teaching that give the learners autonomy search to new ideas, verify them, and restructure existing ideas, I developed a model of conceptual change from where I deduced the four sub variables of the conceptual change that this study explored. The sub variables include formulation of ideas, search for new ideas, review of meaning, and transfer of knowledge. My assumption was that conceptual change can be facilitated through instructions that engage learners in experiences relevant to the four sub variables that I have mentioned. This conceptual framework served as my reference point for the designing of the Constructivist Teaching Model that consists of four instructional phases. Judging that I was resident and working in Seychelles as a teacher trainer at a time I developed the Constructivist Teaching Model, I chose to implement and evaluate it first in Seychelles. Hence this study is titled `The implementation and evaluation of a constructivist intervention in secondary school science teaching in Seychelles'. The purpose of this study is to investigate the effect of the constructivist teaching model as an intervention to facilitate conceptual change. Basically, there are two main aims of this study. First, to investigate to what extent the constructivist teaching model facilitates conceptual change. Secondly, to investigate if the paradigms shift from the traditional method to the constructivist method of science teaching is welcomed in Seychelles. This study was carried out in two phases Pretest and Evaluation. Pretest was aimed at identifying the weaknesses of the initial version of my model of constructivist teaching with a view to eliminate those weaknesses to further strengthen the model. In a nutshell pretest was a step taken to enhance the validity of the model. Evaluation on the other hand was aimed at making a judgment whether a difference actually exists between the learners that received constructivist instruction and those that received traditional lecture instruction in terms of the four sub variables of conceptual change. To enable for this judgment necessitated an experiment. The experiment was conducted with a total of six secondary schools selected from the ten secondary schools on the island. The participants included 178 learners, 6 science teachers and 8 independent persons. The learners were constituted into three Bands; 1, 2 and 3. Each Band consisted of a Control group and an Experimental group. Altogether six groups were formed, with 3 Control groups and 3 Experimental groups. There were 59 learners in Band 1, comprising of 29 learners in the Control group and 30 learners in the Experimental group; Band 2 comprised a Control group of 25 learners and an Experimental group of 28 learners; and Band 3 consisted of 33 learners in each group. The learners in Band 1 were used for pretest that lasted for five week. The learners in Bands 2 and 3 were used in the evaluation that lasted for thirteen weeks. The groups were non-equivalent, suggesting that randomisation was not possible as the learners were in intact classes. Learners in the experimental groups received constructivist instruction while their counterparts in the control groups received traditional lecture instruction. Both groups were exposed to the same experimental conditions except in the methods of teaching. Data was collected through teacher interviews, independent observation, measurement of learners' achievement, and analysis of documents. Quantitative data was analysed using descriptive and inferential statistics. Qualitative data was analysed on the basis of content or meaning of the information given by the respondents. Following the design of this study the performance and achievements of learners that received constructivist instruction were compared with their counterparts who received traditional instruction. Guiding this study are two main assumptions. The first is the assumption of equality of the variance, and the second is the assumption of normality of the distribution. The results of Levene's test of equality of variances indicated a violation of the assumption of homogeneity of the variances of TI and CI groups while the results of test of skewness and kurtosis give the indication of normality of distribution of scores in both groups. The results of descriptive statistics analysis showed that the learners who received constructivist instruction performed better than the learners that received traditional instruction in terms of formulation of ideas, search for new ideas, review of meaning, and transfer of knowledge. The results of inferential statistics showed that the difference in the means of the two groups on each of the sub variables of conceptual change is significant. This evidence indicates that my model of constructivist teaching produced an effect measuring 0.86 and a power of 0.85 based on Cohen's Blueprint, and a reliability of 0.72 based on Cronbach's test of internal consistency. Besides statistical evidence, analysis of the opinions of science teachers who implemented the Constructivist Teaching Model in their respective classes and the independent persons who observed teaching and learning in both the experimental and control groups showed a preference for the constructivist approach over the traditional approach. On the grounds of the evidence gathered through observation and measurement this study concludes that the constructivist approach to science teaching is more effective than traditional lecture approach in facilitating the ability of secondary school learners in Seychelles to reconstruct ideas. This study also found that science educationists in Seychelles welcome the paradigm shift from the traditional approach to the constructivist approach. / Educational Studies / D. Educ. (Psychology of Education)

Lightning as a natural phenomenon is shallowly presented in the Namibian curriculum documents such as the syllabus and textbooks. This gap in curriculum triggered my interest to investigate whether learners’ meaning-making in static electricity was enabled or constrained by elicitation and integration of their cultural beliefs and experiences about lightning and by their practical activities. This study was conducted with my grade 8 learners at the school where I am currently teaching. The school is located in a rural area in Ohangwena region in Northern Namibia. The study is situated within an interpretive paradigm. Within the interpretive paradigm, a qualitative case study approach was adopted. I considered this methodological orientation appropriate in this study as it allowed me to use the following data gathering methods: document analysis, brainstorming, discussions and presentations, semi-structured interview, focus group interview, observation and an assessment test. Multiple methods to gather data were used for triangulation and validation purposes. For data analysis purposes, the data sets were colour-coded to derive themes and analytical statements. Ethical considerations were also taken seriously in this study and all participants gave consent. An analysis of data revealed that there is no learning objective or basic competence in the Namibian Physical Science syllabus for grade 8-10 that requires learners to bring in their cultural beliefs and experiences, in particular, about lightning. Yet the study revealed that learners possess a lot of prior everyday scientific and non-scientific knowledge and experiences about lightning that they had acquired from their communities. Also, mobilization of learners' everyday knowledge and experiences about lightning enabled learner engagement during the science lessons. Likewise, engaging learners in practical activities in static electricity helped them to make meaning of scientific concepts. Based on my research findings, I therefore, recommend that learners' prior everyday knowledge and experiences about lightning should be incorporated during teaching and learning of the topic on static electricity.

published_or_final_version / abstract / toc / Education / Doctoral / Doctor of Philosophy

published_or_final_version / Education / Master / Master of Education

published_or_final_version / Education / Master / Master of Education

Test items supplied with seven textbooks approved for use in Computer Science I and II curricula in Texas public schools were categorized by Bloom's taxonomy of educational objectives. Eating was done by a panel of ten judges selected from a group of participants at a taxonomy workshop. The selection criterion was demonstration of at least 80 percent competency in item classification. Judges received a small stipend for completing the rating task. Of 2020 possible items, 998 were randomly selected for analysis. Equal percentages of items from each text were then randomly assigned to each rater. All statistical analyses were computed using SPSS/PC+ (version 2.1). In both courses, CLD frequencies decreased through the three lower levels. The percentage of questions falling in these levels was approximately 83 percent for both courses. However, the higher-level course contained almost 10 percent more Knowledge level questions than did the lower course. At the higher taxonomic levels, the decline was roughly five percent per level in CS I but erratic in CS II. Analysis by book also revealed wide differences within each course.

M.Ed. / Computer Studies as a school subject consists of a theory and a practical component. The practical component refers to programming. In programming the student has to design a algorithm. Problems can be solved with step by step approaches which lead to the final instruction that will solve the problem. This sequence of instructions that lead to problem solving is called an algorithm. There is more than one algorithm that will solve the same problem. There is no fixed recipe but only guidelines that assist the student to design an algorithm. During the designing of an algorithm the student gets the opportunity to be creative. The practical component of computer studies provides the ideal situation in which the student can solve a problem in his own way. Because of the nature of computer studies which is problem solving the opportunity arises where one can expose his creative talent. The situation unfortunately today exists where some teachers lack experience and training. To determine whether a specific algorithm solves a problem the inexperienced teacher should use a computer. Teachers that prefer to mark algorithms with a memorandum hamper the creativity of students. Although most teachers do have the necessary academic background they were not properly trained in the subject didactics of computer studies.