對話與思考:如何提升你的數(shù)學思維?
自然界與現(xiàn)實社會,在諸多方面展現(xiàn)著數(shù)學思維的運用。但是在教學中,怎樣將現(xiàn)實問題轉(zhuǎn)化到數(shù)學課堂?以何種視角建構(gòu)起現(xiàn)實問題與數(shù)學問題之間的聯(lián)系?
蘇城外國語學校高中部的數(shù)學課堂有著屬于自己的闡釋與演繹。
The application of Mathematics can been seen everywhere in the real world. The Mathematics class in the SCFLS senior high school has its own interpretation for turning real-life questions into Maths problems, and the connection between these two.
教師簡介 Teacher Profile
在這節(jié)課之前,學生已經(jīng)學習了一些關(guān)于直線的基本知識,比如如何求直線的表達式,斜率的意義,如何通過表達式畫出對應直線等。
教學目標:
讀懂散點圖,通過數(shù)據(jù)畫出散點圖。
在散點圖中找出最佳擬合直線,并求出表達式。
Before this class, students have had some prior knowledge, for example: how to find the linear function, the meaning of slope and how to draw the corresponding line of a given function. Based on these, the teaching objectives are:
To understand and draw the scatter plot of given data.To find the line of best fit for the scatter plot and find the equation
教師呈現(xiàn)出一組關(guān)于學生每周學習數(shù)學的時間和學生期中考試成績的數(shù)據(jù),引導學生根據(jù)這一組數(shù)據(jù)畫出散點圖。然后讓每一組學生思考這一組數(shù)據(jù)兩個量之間的關(guān)系和如何能夠添加輔助線來描述這兩個量之間的趨勢,并同時在紙上畫出,以此來鍛煉他們作為Inquirers,Thinkers的能力。
Teacher presented a set of data about students’ weekly study time in math and the mid-term math score of each student, guiding students to draw the scatter plot based on the given data. After that, students were encouraged to think what could be added to describe the trend between these two variables and show it on paper. Through this activity, they were trained to be inquirers and thinkers.
同學們經(jīng)過思考得出不一樣的結(jié)論,老師在黑板上展示了幾張不同的答案,同學們也相互討論,投票選出他們認為最能描述兩個量之間趨勢的圖,在這一過程中,充分展現(xiàn)了學生們communicators與open-minded的特質(zhì)。
After discussion, different answers were presented by teacher on the blackboard. Students had to justify their answers and voted for the best graph, demonstrating their abilities as communicators and open-minded.
老師提取同學們討論中的關(guān)鍵信息,正是這一節(jié)課的教學重點,并延伸開去講解如何挑選最佳擬合直線,什么是預測函數(shù),如何求解預測函數(shù),如何利用預測函數(shù)來解決實際問題。老師精當?shù)闹v解可以讓學生更加knowledgeable。
Teacher extracted the key point of student’s discussion and extended to the topic: how to choose the line of best fit and prediction function and applications in real life. Students will be more knowledgeable with teacher’s explanation.
教師在課堂中對學生進行再次分組,從原來有利于促進討論的異質(zhì)分組換為同質(zhì)分組,根據(jù)每組學生不同的學習能力分配難度不同的習題,能力最強的一組除了基礎的練習,會補充更開放的思考題。
Students were regrouped according to homogeneous intelligences, and assigned with tasks of different levels. The higher-level group had more open-ended questions apart from some basic problems.
任何的數(shù)學模型都有它的局限性,這節(jié)課學習的直線預測模型也不例外。學生要結(jié)合他們這堂課的學習知識和現(xiàn)實生活經(jīng)驗來思考直線模型的局限性。直線模型只能用來預測一定范圍內(nèi)的數(shù)據(jù),當自變量很大時就會變得不準確。比如學習的時間變長,成績也不會超過試卷的滿分;也可能直線模型并不是描述關(guān)系的最佳選擇。
Restrictions exist in any mathematical model, so does the model in this class. Students discussed the restriction based on the real-life experience and knowledge in this class. Here are some possible answers: the linear prediction function only works in a suitable range; the linear model is not the best choice.
中文撰稿:顧佳玲
英文翻譯:沈紫煙
攝影:宋柏霖
英文審核:語言中心
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