Abstracts of Presentations
Making sense of teachers’ design of instructional materials
Number sense has been highlighted as a vital prerequisite to success in mathematics. As such, the development of number sense plays a key role in mathematics education. To develop students with good number sense, teachers not only need to equip themselves with strategies that can foster number sense, but also assessment methods that can obtain rich knowledge of students’ number sense abilities. Research has suggested the use of journal writing to access to students’ number sense but there seems to be a lack of studies exploring the use of journal writing as a tool to assess students’ number sense. Using a case study methodology, this study investigated the affordances of journal writing in eliciting students’ number sense. Four different journal tasks were given to 94 Primary 5 students who were studying in a typical Singapore government school. These tasks were designed with appropriate writing prompts and aligned to the different components of number sense to allow students to demonstrate their number sense abilities. Other than students’ journal entries, their Primary 4 year-end assessment results were also collected as part of the data for the study. Eventually, a total of 16 journal entries from four students were analysed in depth using thematic analysis to surface possible affordances of journal writing through their writings. Analysis of students’ journal entries revealed that journal writing offers a ‘window’ into understanding students’ number sense through three different lenses. Findings from the study suggested that these three affordances of journal writing are: (1) revealing students’ conceptions and misconceptions of numbers and operations, (2) making students’ thinking processes visible and (3) manifesting students’ flexibility with numbers and operations. Such information on students’ number sense may not have surfaced from a paper-and-pencil assessment. In fact, it was found that good performance in summative paper-and-pencil assessment does not necessarily equate to good number sense abilities and vice versa. Thus, teachers need to examine beyond answers to gain a better understanding of students’ understanding and thinking of numbers and operations. In this study, it is evident that journal writing can provide that avenue. Evidence from students’ journals also supported the use of different types of journal writing to elicit a variety of responses from students so as to have a better picture of the students’ number sense abilities. This study provided some designs of tasks that teachers and teacher educators could use as authentic examples. Other implications include contributing to the existing literature on journal writing and assessment of number sense, especially in local context, to trigger more conversations and create greater awareness among teachers.
Studies have indicated that the demand for proofs is significantly different between secondary school and university mathematics. This study explored the ideas of proof in a secondary school textbook. Volume A and B of “Additional Maths 360” textbook published by Marshall Cavendish Education was used. The content, worked examples and extent questions in this textbook were analysed and proofs were categorized according to their adopted presentation. Use of examples emerged as the most common approach for illustrating proofs. The discussion centers on the pedagogical and learning implications for teachers and students, respectively.
Use of instructional materials in secondary school mathematics lessons
The talk will introduce and define relevant concepts, and survey the topic of Hamilton decompositions of graphs. Some new results that we have recently obtained in this area will then be presented.
Statistics on Ascent Sequences
High-dimensional spectroscopic data is informative, and has applications in many fields such as biomedical sciences and food science. The fitting of regression models for the purposes of prediction is known to be a challenging task due to the high-dimension of the datasets, as well as high correlation between wavenumbers in the data. One method that has gained interest in recent years is the use of regularization to overcome these challenges. In this talk, we present a regularized model for spectroscopic data. Depending on the penalty functions used in the regularized model, different computational challenges may arise. We will discuss some algorithms that are of interest in solving for such regularized model coefficients, as well as the advantages and disadvantages of these algorithms.
A Haskell Implementation of the Lyness-Moler's Numerical Differentiation Algorithm