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151.
Ilana Lavy 《The Journal of Mathematical Behavior》2010,29(1):11-24
In the present study we explore changes in perceptions of our class of prospective mathematics teachers (PTs) regarding their mathematical knowledge. The PTs engaged in problem posing activities in geometry, using the “What If Not?” (WIN) strategy, as part of their work on computerized inquiry-based activities. Data received from the PTs’ portfolios reveals that they believe that engaging in the inquiry-based activity enhanced both their mathematical and meta-mathematical knowledge. As to the mathematical knowledge, they deepened their knowledge regarding the geometrical concepts and shapes involved, and during the process of creating the problem and checking its validity and its solution, they deepened their understanding of the interconnections among the concepts and shapes involved. As to meta-mathematical knowledge, the PTs refer to aspects such as the meaning of the givens and their relations, validity of an argument, the importance and usefulness of the definitions of concepts and objects, and the importance of providing a formal proof. 相似文献
152.
The purpose of this paper is to further the notion of defining as a mathematical activity by elaborating a framework that structures the role of defining in student progress from informal to more formal ways of reasoning. The framework is the result of a retrospective account of a significant learning experience that occurred in an undergraduate geometry course. The framework integrates the instructional design theory of Realistic Mathematics Education (RME) and distinctions between concept image and concept definition and offers other researchers and instructional designers a structured way to analyze or plan for the role of defining in students’ mathematical progress. 相似文献
153.
This paper reports on the forms of reasoning elicited as fourth grade students in a suburban district and sixth grade students in an urban district worked on similar tasks involving reasoning with the use of Cuisenaire rods. Analysis of the two data sets shows similarities in the reasoning used by both groups of students on specific tasks, and the tendency of a particular task to elicit numerous forms of reasoning in both groups of students. Attributes of that task and ways that those attributes can be replicated in other domains may have implications in the teaching of early reasoning. 相似文献
154.
155.
MOOCs正以其巨大的浪潮冲击着当今的高等教育.本文根据国内外MOOCs的发展现状,综合分析了MOOCs的优势及其对教学模式带来的影响,结合我们正在开展的大学物理MOOCs建设,提出了在课程改革中需要重点关注的四个方面,以期有助于更好地迎接MOOCs的挑战. 相似文献
156.
Norbert Hungerbühler 《International Journal of Mathematical Education in Science & Technology》2013,44(4):483-492
Based on Kepler's laws we calculate the position of the sun as a function of the date, the local time, the latitude and longitude and use the resulting formula to construct a portable sundial which works without being adjusted to the cardinal directions (i.e. there is no need for an additional compass). 相似文献
157.
David Ginat 《International Journal of Mathematical Education in Science & Technology》2013,44(5):635-651
Loop invariants are assertions of regularities that characterize the loop components of algorithms. They are fundamental components of computerprograms verification, but their relevance goes beyond verification—they can be significantly utilized for algorithm design and analysis. Unfortunately, they are only modestly introduced in the teaching of programming and algorithms. One reason for this is an unjustified notion that loop invariants are ‘tied to formality’, hard to illustrate, and difficult to comprehend. In this paper a novel approach is presented for illustrating on a rather intuitive level the significance of loop invariants. The illustration is based on mathematical games, which are attractive examples that require the exploration of regularities via problemsolving heuristics. Throughout the paper students' application of heuristics is described and emphasis is placed on the links between loop invariants, heuristic search activities, recognition of regularities and design and analysis of algorithms. 相似文献
158.
Temple H. Fay Sarah Duncan Graham 《International Journal of Mathematical Education in Science & Technology》2013,44(1):65-79
Coupled spring equations for modelling the motion of two springs with weights attached, hung in series from the ceiling are described. For the linear model using Hooke's Law, the motion of each weight is described by a fourth-order linear differential equation. A nonlinear model is also described and damping and external forcing are considered. The model has many features that permit the meaningful introduction of many concepts including: accuracy of numerical algorithms, dependence on parameters and initial conditions, phase and synchronization, periodicity, beats, linear and nonlinear resonance, limit cycles, harmonic and subharmonic solutions. These solutions produce a wide variety of interesting motions and the model is suitable for study as a computer laboratory project in a beginning course on differential equations or as an individual or a small-group undergraduate research project. 相似文献
159.
Ralph-Johan Back Solveig Wallin 《International Journal of Mathematical Education in Science & Technology》2013,44(5):575-593
In this article, we present the results from a qualitative study on students' initial reactions to the use of structured derivations in mathematics education. Our findings suggest that the approach increases the clarity of solutions and facilitates debugging of proofs. It also has potential to increase students' self-perceived level of understanding. Our findings indicate that the main drawbacks experienced by the students are related to time and length. Nevertheless, the overall feedback on the approach was found to be positive, thus encouraging further use of structured derivations in mathematics education. 相似文献
160.
Tom Bourner Asher Rospigliosi 《International Journal of Mathematical Education in Science & Technology》2013,44(6):777-793
This article is about what happens to newly minted mathematics graduates. It explores data from the first destination statistics from the perspective of mathematics lecturers and others involved in institutions that provide a higher education in mathematics. It also looks at reasons why this issue is important to those engaged in the higher education of mathematics undergraduates. A key finding is that the employment of mathematics graduates is concentrated in the sector of the economy that includes banking, property and financial services which makes the employment prospects for new graduates in mathematics vulnerable to recession in that sector. 相似文献