Reflections on digital technologies in mathematics education across cultures

C. Hoyles, Carolyn Kieran, T. Rojano, A. I. Sacristán, M. Trigueros
{"title":"Reflections on digital technologies in mathematics education across cultures","authors":"C. Hoyles, Carolyn Kieran, T. Rojano, A. I. Sacristán, M. Trigueros","doi":"10.51272/pmena.42.2020-1","DOIUrl":null,"url":null,"abstract":"ion process” (p. 1). Relevant to the questions addressed to this panel, she adds that computational thinking can be defined as “the thought processes involved in formulating a problem and expressing (with a linguistic representation) its solution in such a way that a computer – human or machine – can effectively carry it out” (p. 1). Interestingly, Andy diSessa (2018) – one of the two authors of Turtle Geometry back in 1981 – has taken issue with this point and has argued that noncomputer scientists rarely map out exactly how a problem can be solved before actually doing the solving. But is he right? In opposition to diSessa, and more in line with Wing, Al Cuoco (2018) in a paper on mathematical practice offers three examples. The first of these (see Fig. 1) relates to Wing’s emphasis on the process of abstraction and her point about formulating a problem and expressing its solution in a way that a computing being or machine can carry it out. This example involves what Cuoco refers to as “the dreaded algebra word problem,” where he insists that we think of the answer to the algebra problem as an equation rather than a number – in a method that involves abstracting from numerals. The problem is as follows: “Mary drives from Boston to Chicago, travels at an average rate of 60 MPH on the way down and 50 MPH on the way back. The total driving time takes 36 hours, how far is Boston from Chicago?” Figure 1. Arriving at an equation from abstracting the regularity in numerical guesses (Cuoco, 2018, p. 3) The method that Cuoco suggests builds upon students’ ability to solve similar problems in middle school (note: they have already learned the relationship between speed, time, and distance) and is as follows: Take a guess – but the aim is not intended to get closer to the answer with each succeeding guess; rather it is to arrive at an equation, not a number. The idea is to carry out enough guesses so as to see the regularity of the calculations that allow for checking the guesses – in Cuoco’s words: Develop “a generic ‘guess checker’ that is the desired equation”. The processes of mathematical Reflections on digital technologies in mathematics education across cultures 76 practice that are employed here, and which are ones that Cuoco declares he uses all the time in his own mathematical work, are: 1. Abstract regularity from repeated calculations, and 2. Use precise language (and algebraic symbolism) to give a generic and general description – the equation – for how you check your guesses. (Cuoco, 2018, p. 4) The conclusion to be drawn from this example is that these two processes of mathematical practice fit well with the programming and thinking-like-a-programmer characteristics of computational thinking (Wing, 2006, 2014), and that students who are currently engaged in using digital technologies (e.g., laptops, robots) to code with visual (e.g., Scratch) or text-based languages are participating in mathematical practices. Nevertheless, other research (e.g., Bråting & Kilhamn, 2020) suggests that, while the representations used in programming languages may be similar to mathematical notations, the meanings of several concepts in the two domains differ. But that is a whole other story! In any case, digital technologies afford multiple varieties of mathematical activity that can offer experiences that involve coding but also those that do not. Some Canadian research on the use of digital technologies to foster mathematical thinking I take mathematical thinking to include the various processes that have been drawn upon by Wing and others to characterize aspects of computational thinking – but also more than this, for example, its conceptual aspects. While computational thinking is focused toward coding, mathematical thinking occurs within a host of activities that are not coding oriented, but which can clearly be engaged in within specifically-designed digital environments. However, the tricky thing about terms such as computational thinking and mathematical thinking is their overlap when referring to anything mathematical. Moreover, as Cuoco (2018, p. 2) has pointed out: “In real mathematical practice, it is rare that a piece of work employs only one aspect of mathematical thinking” – and, similarly, only one aspect of computational thinking. Despite the obvious intersection between the two terms, I find it helpful when discussing the use of digital technologies in mathematical activity to distinguish between coding-related activity and non-coding-related activity. In line with this distinction, I offer some examples that give a flavour of Canadian research that has focused on these two types of activity, both of which have successfully combined selected aspects of computational thinking and of mathematical thinking. Digital Technologies in Coding-Related Mathematical Activity Scratch coding on laptops. My first example is drawn from the funded, multi-study research project of George Gadanidis and colleagues from across Canada, titled Computational Thinking in Mathematics Education – a project aimed at researching the use of computational thinking (via, e.g., digital tangibles such as circuits, programmable robots, and coding with Scratch on laptops) in mathematics education, from pre-school to undergraduate mathematics, and in mathematics teacher education (see ctmath.ca/about). In one of the publications from this project (Gadanidis et al., 2017), the initial activity engaged in by the Grade 1 students of a school in Ontario was the use of the blockbased, visual programming language, Scratch (available at http://scratch.mit.edu), for exploring squares by drawing a set of squares rotated around a point (see Fig. 2; see also Gadanidis, 2015). One of the fundamental principles underpinning these study projects is connecting the digital technology work in classrooms to the math curriculum that teachers need to teach. Reflections on digital technologies in mathematics education across cultures 77 Figure 2: Scratch coding in Grade 1 (from Gadanidis et al., 2017, p. 81) Figure 3. Programming a robot using loops (from Francis & Davis, 2018, p. 82) Coding robots. Francis and Davis (2018) studied 9and 10-year-olds’ understanding of number, and the transition from additive to multiplicative thinking, in the context of learning to build and program Lego Mindstorms EV3 robots. The sequence of tasks focused on students’ becoming aware of the architecture of robots, programming the robots to trace a triangle, square, pentagon, or hexagon; and building a robot that could find and douse a ‘fire’ in any of four rooms of a miniature model building. In one of the scenarios that Francis and Davis report on, a student learns how the number of sides and angles of a polygon connects to the number of repeats in a loop, which illustrates a developing shift from thinking additively in terms of a sequence of like actions to thinking multiplicatively in terms of a repetition of a single action (see Fig. 3). The authors argue that coding-related activity with digital technologies can co-amplify mathematics learning, as long as computer programming is seen as “something for” and is integrated into the existing curriculum with well-designed tasks, not as “something more” in a separate curriculum. Digital Technologies in Non-Coding-Related Mathematical Activity Figure 4. TouchCounts App: upper -10 tap; lower -result of 10 single taps (Rodney, 2019, p. 169) Figure 5. “Five Steps to Zero,” with a starting number of 151 (adapted from Williams & Stephens, 1992) TouchCounts – an iPad touchscreen App. The TouchCounts application software, developed by Sinclair and Jackiw (2014), served as a window for the researcher Rodney (2019) to study how a 5and-a-half-year-old, Auden, thought about number. Although Auden was able to say the number names initially, he seemed unaware that the written numeral ‘10’ would appear right after ‘9’ and Reflections on digital technologies in mathematics education across cultures 78 that ‘10’ also represented the number of taps made on the iPad screen (see Fig. 4). Auden’s unsuccessful initial activity with the App revealed that his memorized number chanting needed the further support that TouchCounts could afford in order to reach a fuller understanding of counting and to begin to identify the relational aspect of numbers. Calculators with multi-line screens. Calculators remain a staple in many mathematics classes. This resource, one with a multi-line screen, served as the digital tool underpinning a study that focused on the mathematical practice of seeking, using, and expressing structure in numbers and numerical operations (Kieran, 2018). The study (co-conducted with José Guzman†) involved classes of 12-year-old Mexican students on tasks adapted from the “Five Steps to Zero” problem (Williams & Stephens, 1992; see Fig. 5). Successfully tackling the designed tasks, and subject to the rules of the game, involved developing techniques for reformulating numbers (prime or composite) into other numbers in the same neighbourhood (not more than 9 away from the given number) that have divisors not larger than 9 so as to reach zero in five or fewer steps. Some of the most powerful structural explorations that occurred during the week of activity on the tasks involved the search for multiples of 9. For example, students became aware that “738 and 729 are two adjacent multiples of 9 and, when they are both divided by 9, the quotients are consecutive,” and “in the 9-number interval from 735 to 743 inclusive, there is exactly one number divisible by 9.” In trying to explain the oftensurprising results produced by their digital tools, the students developed several mathematical insights that were new to them. Carolyn Kieran’s concluding remarks My concluding remarks pick up on the interest shown by students in the use of digital technologies – be they coding-related or not. For example, Gadanidis et al. 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引用次数: 1

Abstract

ion process” (p. 1). Relevant to the questions addressed to this panel, she adds that computational thinking can be defined as “the thought processes involved in formulating a problem and expressing (with a linguistic representation) its solution in such a way that a computer – human or machine – can effectively carry it out” (p. 1). Interestingly, Andy diSessa (2018) – one of the two authors of Turtle Geometry back in 1981 – has taken issue with this point and has argued that noncomputer scientists rarely map out exactly how a problem can be solved before actually doing the solving. But is he right? In opposition to diSessa, and more in line with Wing, Al Cuoco (2018) in a paper on mathematical practice offers three examples. The first of these (see Fig. 1) relates to Wing’s emphasis on the process of abstraction and her point about formulating a problem and expressing its solution in a way that a computing being or machine can carry it out. This example involves what Cuoco refers to as “the dreaded algebra word problem,” where he insists that we think of the answer to the algebra problem as an equation rather than a number – in a method that involves abstracting from numerals. The problem is as follows: “Mary drives from Boston to Chicago, travels at an average rate of 60 MPH on the way down and 50 MPH on the way back. The total driving time takes 36 hours, how far is Boston from Chicago?” Figure 1. Arriving at an equation from abstracting the regularity in numerical guesses (Cuoco, 2018, p. 3) The method that Cuoco suggests builds upon students’ ability to solve similar problems in middle school (note: they have already learned the relationship between speed, time, and distance) and is as follows: Take a guess – but the aim is not intended to get closer to the answer with each succeeding guess; rather it is to arrive at an equation, not a number. The idea is to carry out enough guesses so as to see the regularity of the calculations that allow for checking the guesses – in Cuoco’s words: Develop “a generic ‘guess checker’ that is the desired equation”. The processes of mathematical Reflections on digital technologies in mathematics education across cultures 76 practice that are employed here, and which are ones that Cuoco declares he uses all the time in his own mathematical work, are: 1. Abstract regularity from repeated calculations, and 2. Use precise language (and algebraic symbolism) to give a generic and general description – the equation – for how you check your guesses. (Cuoco, 2018, p. 4) The conclusion to be drawn from this example is that these two processes of mathematical practice fit well with the programming and thinking-like-a-programmer characteristics of computational thinking (Wing, 2006, 2014), and that students who are currently engaged in using digital technologies (e.g., laptops, robots) to code with visual (e.g., Scratch) or text-based languages are participating in mathematical practices. Nevertheless, other research (e.g., Bråting & Kilhamn, 2020) suggests that, while the representations used in programming languages may be similar to mathematical notations, the meanings of several concepts in the two domains differ. But that is a whole other story! In any case, digital technologies afford multiple varieties of mathematical activity that can offer experiences that involve coding but also those that do not. Some Canadian research on the use of digital technologies to foster mathematical thinking I take mathematical thinking to include the various processes that have been drawn upon by Wing and others to characterize aspects of computational thinking – but also more than this, for example, its conceptual aspects. While computational thinking is focused toward coding, mathematical thinking occurs within a host of activities that are not coding oriented, but which can clearly be engaged in within specifically-designed digital environments. However, the tricky thing about terms such as computational thinking and mathematical thinking is their overlap when referring to anything mathematical. Moreover, as Cuoco (2018, p. 2) has pointed out: “In real mathematical practice, it is rare that a piece of work employs only one aspect of mathematical thinking” – and, similarly, only one aspect of computational thinking. Despite the obvious intersection between the two terms, I find it helpful when discussing the use of digital technologies in mathematical activity to distinguish between coding-related activity and non-coding-related activity. In line with this distinction, I offer some examples that give a flavour of Canadian research that has focused on these two types of activity, both of which have successfully combined selected aspects of computational thinking and of mathematical thinking. Digital Technologies in Coding-Related Mathematical Activity Scratch coding on laptops. My first example is drawn from the funded, multi-study research project of George Gadanidis and colleagues from across Canada, titled Computational Thinking in Mathematics Education – a project aimed at researching the use of computational thinking (via, e.g., digital tangibles such as circuits, programmable robots, and coding with Scratch on laptops) in mathematics education, from pre-school to undergraduate mathematics, and in mathematics teacher education (see ctmath.ca/about). In one of the publications from this project (Gadanidis et al., 2017), the initial activity engaged in by the Grade 1 students of a school in Ontario was the use of the blockbased, visual programming language, Scratch (available at http://scratch.mit.edu), for exploring squares by drawing a set of squares rotated around a point (see Fig. 2; see also Gadanidis, 2015). One of the fundamental principles underpinning these study projects is connecting the digital technology work in classrooms to the math curriculum that teachers need to teach. Reflections on digital technologies in mathematics education across cultures 77 Figure 2: Scratch coding in Grade 1 (from Gadanidis et al., 2017, p. 81) Figure 3. Programming a robot using loops (from Francis & Davis, 2018, p. 82) Coding robots. Francis and Davis (2018) studied 9and 10-year-olds’ understanding of number, and the transition from additive to multiplicative thinking, in the context of learning to build and program Lego Mindstorms EV3 robots. The sequence of tasks focused on students’ becoming aware of the architecture of robots, programming the robots to trace a triangle, square, pentagon, or hexagon; and building a robot that could find and douse a ‘fire’ in any of four rooms of a miniature model building. In one of the scenarios that Francis and Davis report on, a student learns how the number of sides and angles of a polygon connects to the number of repeats in a loop, which illustrates a developing shift from thinking additively in terms of a sequence of like actions to thinking multiplicatively in terms of a repetition of a single action (see Fig. 3). The authors argue that coding-related activity with digital technologies can co-amplify mathematics learning, as long as computer programming is seen as “something for” and is integrated into the existing curriculum with well-designed tasks, not as “something more” in a separate curriculum. Digital Technologies in Non-Coding-Related Mathematical Activity Figure 4. TouchCounts App: upper -10 tap; lower -result of 10 single taps (Rodney, 2019, p. 169) Figure 5. “Five Steps to Zero,” with a starting number of 151 (adapted from Williams & Stephens, 1992) TouchCounts – an iPad touchscreen App. The TouchCounts application software, developed by Sinclair and Jackiw (2014), served as a window for the researcher Rodney (2019) to study how a 5and-a-half-year-old, Auden, thought about number. Although Auden was able to say the number names initially, he seemed unaware that the written numeral ‘10’ would appear right after ‘9’ and Reflections on digital technologies in mathematics education across cultures 78 that ‘10’ also represented the number of taps made on the iPad screen (see Fig. 4). Auden’s unsuccessful initial activity with the App revealed that his memorized number chanting needed the further support that TouchCounts could afford in order to reach a fuller understanding of counting and to begin to identify the relational aspect of numbers. Calculators with multi-line screens. Calculators remain a staple in many mathematics classes. This resource, one with a multi-line screen, served as the digital tool underpinning a study that focused on the mathematical practice of seeking, using, and expressing structure in numbers and numerical operations (Kieran, 2018). The study (co-conducted with José Guzman†) involved classes of 12-year-old Mexican students on tasks adapted from the “Five Steps to Zero” problem (Williams & Stephens, 1992; see Fig. 5). Successfully tackling the designed tasks, and subject to the rules of the game, involved developing techniques for reformulating numbers (prime or composite) into other numbers in the same neighbourhood (not more than 9 away from the given number) that have divisors not larger than 9 so as to reach zero in five or fewer steps. Some of the most powerful structural explorations that occurred during the week of activity on the tasks involved the search for multiples of 9. For example, students became aware that “738 and 729 are two adjacent multiples of 9 and, when they are both divided by 9, the quotients are consecutive,” and “in the 9-number interval from 735 to 743 inclusive, there is exactly one number divisible by 9.” In trying to explain the oftensurprising results produced by their digital tools, the students developed several mathematical insights that were new to them. Carolyn Kieran’s concluding remarks My concluding remarks pick up on the interest shown by students in the use of digital technologies – be they coding-related or not. For example, Gadanidis et al. (2017) emphasize “learning experie
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跨文化数学教育中数字技术的思考
与向这个小组提出的问题相关,她补充说,计算思维可以被定义为“以一种计算机——人或机器——可以有效地执行的方式,制定问题并表达(用语言表示)其解决方案所涉及的思维过程”(第1页)。Andy diSessa(2018)——1981年《海龟几何》的两位作者之一——对这一点提出了异议,他认为非计算机科学家很少在实际解决问题之前准确地绘制出如何解决问题。但他是对的吗?Al Cuoco(2018)在一篇关于数学实践的论文中提供了三个例子,与diSessa相反,更符合Wing的观点。第一点(见图1)涉及到Wing对抽象过程的强调,以及她提出的以计算生物或机器可以执行的方式提出问题并表达其解决方案的观点。这个例子涉及到Cuoco所说的“可怕的代数问题”,他坚持认为我们应该把代数问题的答案看作一个方程,而不是一个数字——用一种从数字中抽象出来的方法。问题是这样的:“玛丽开车从波士顿到芝加哥,去的时候平均速度是每小时60英里,回来的时候平均速度是每小时50英里。开车总共需要36个小时,波士顿到芝加哥有多远?”图1所示。通过抽象数值猜测的规律性来得出方程(Cuoco, 2018,第3页)。Cuoco建议的方法建立在学生在中学解决类似问题的能力基础上(注意:他们已经学会了速度、时间和距离之间的关系),方法如下:进行猜测——但目的不是为了在每次猜测中更接近答案;而是要得到一个方程,而不是一个数字。这个想法是进行足够多的猜测,以便看到计算的规律性,从而可以检查猜测-用库柯的话来说:开发“一个通用的'猜测检查器',即所需的方程”。本文采用的是跨文化数学教育中数字技术的数学反思过程76个实践,库柯声称他在自己的数学工作中一直使用这些实践。从重复计算中抽象出规律性;使用精确的语言(和代数符号)给出一个通用的和一般的描述-方程-你如何检查你的猜测。(Cuoco, 2018,第4页)从这个例子中得出的结论是,这两个数学实践过程非常符合计算思维的编程和像程序员一样思考的特征(Wing, 2006, 2014),并且目前从事使用数字技术(例如笔记本电脑,机器人)使用视觉(例如Scratch)或基于文本的语言进行编码的学生正在参与数学实践。然而,其他研究(例如,bramatting & Kilhamn, 2020)表明,虽然编程语言中使用的表示可能类似于数学符号,但这两个领域中几个概念的含义不同。但那完全是另一回事了!无论如何,数字技术提供了多种数学活动,这些活动可以提供涉及编码的体验,也可以提供不涉及编码的体验。我认为数学思维包括了Wing和其他人用来描述计算思维特征的各种过程——但也不止于此,例如,它的概念方面。计算思维侧重于编码,而数学思维则发生在一系列不以编码为导向的活动中,但这些活动显然可以在专门设计的数字环境中进行。然而,计算思维和数学思维等术语的棘手之处在于,它们在涉及任何数学问题时都是重叠的。此外,正如Cuoco (2018, p. 2)指出的那样:“在真正的数学实践中,很少有一项工作只采用数学思维的一个方面”——同样,也只有计算思维的一个方面。尽管这两个术语之间有明显的交集,但我发现在讨论数字技术在数学活动中的使用时,区分与编码相关的活动和与非编码相关的活动是有帮助的。根据这一区别,我提供了一些例子来说明加拿大的研究,这些研究集中在这两种类型的活动上,这两种活动都成功地结合了计算思维和数学思维的某些方面。与编码相关的数学活动中的数字技术——在笔记本电脑上Scratch编码。 我的第一个例子来自于George Gadanidis和他来自加拿大各地的同事资助的多学科研究项目,名为“数学教育中的计算思维”——该项目旨在研究计算思维(通过电路、可编程机器人和笔记本电脑上的Scratch编码等数字有形产品)在数学教育中的应用,从学前到本科数学,以及数学教师教育(见ctmath.ca/about)。在该项目的一份出版物中(Gadanidis et al., 2017),安大略省一所学校的一年级学生参与的最初活动是使用基于块的可视化编程语言Scratch(可在http://scratch.mit.edu上获得),通过绘制一组围绕点旋转的正方形来探索正方形(见图2;另见Gadanidis, 2015)。支撑这些研究项目的基本原则之一是将课堂上的数字技术工作与教师需要教授的数学课程联系起来。图2:一年级学生的Scratch编码(来自Gadanidis等人,2017年,第81页)使用循环编程机器人(来自Francis & Davis, 2018年,第82页)。Francis和Davis(2018)在学习构建和编程Lego Mindstorms EV3机器人的背景下,研究了9岁和10岁儿童对数字的理解,以及从加法思维到乘法思维的转变。任务的顺序集中在让学生意识到机器人的结构,编程机器人跟踪三角形、正方形、五边形或六边形;建造一个机器人,它可以在一个微型模型建筑的四个房间中的任何一个房间找到并扑灭“火”。在Francis和Davis报告的一个场景中,学生学习多边形的边和角的数量如何与循环中重复的数量联系起来,这说明了从类似动作序列的加法思维到单个动作重复的乘法思维的发展转变(见图3)。作者认为,与数字技术相关的编码活动可以共同放大数学学习。只要计算机编程被视为“某件事”,并与设计良好的任务整合到现有课程中,而不是在单独的课程中作为“更多的事情”。非编码相关数学活动中的数字技术TouchCounts App:上-10点;低- 10个单孔的结果(Rodney, 2019, p. 169)图5。TouchCounts——一款iPad触摸屏应用程序。由Sinclair和Jackiw(2014年)开发的TouchCounts应用软件,为研究人员罗德尼(2019年)提供了一个窗口,研究5岁半的奥登是如何思考数字的。虽然奥登一开始能说出几个名字,他似乎没有意识到,书写的数字“10”会出现在“9”之后,而数字技术在跨文化数学教育中的反思78,“10”也代表了在iPad屏幕上点击的次数(见图4)。奥登最初使用该应用程序的失败表明,他记忆的数字诵读需要TouchCounts能够提供的进一步支持,以便更全面地理解计数,并开始识别关系方面数字。多行屏幕计算器。计算器仍然是许多数学课上的主要工具。该资源具有多行屏幕,是一项研究的数字工具,该研究侧重于在数字和数值运算中寻找、使用和表达结构的数学实践(Kieran, 2018)。这项研究(与jos<s:1> Guzman共同进行)涉及12岁的墨西哥学生的班级,他们的任务改编自“五步走向零”问题(Williams & Stephens, 1992;成功地完成设计的任务,并遵守游戏规则,涉及开发技术,将数字(素数或合数)重新表述为相同邻域(距离给定数字不超过9)的其他数字,这些数字的除数不大于9,以便在五步或更少的步骤中达到零。在一周的任务活动中,发生了一些最强大的结构探索,包括寻找9的倍数。例如,学生们意识到“738和729是9的两个相邻倍数,当它们都被9整除时,商是连续的”,以及“在735到743的9个数区间内,只有一个数能被9整除。”在试图解释他们的数字工具产生的经常令人惊讶的结果时,学生们发展了一些对他们来说是新的数学见解。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
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