三角形分类案例(国外英语资料).docVIP

三角形分类案例(国外英语资料) A case of triangle classification The new curriculum requires the transformation of simple reception learning method, the organic combination of independent research and practice experience, promote cooperation and exchange of learning and receptive learning style, advocating do and want, speak the organic unity of the learning process. In order to better achieve the teaching objectives, it is necessary to attract students to participate actively in learning, and to skillfully design and enrich mathematical activities which are suitable for students cognitive rules. Fragment 1: classification of triangles -- by angle D: can you draw a few triangles again to make it different in the shape of the three angles from the triangle just now? Can you draw a two angle or two obtuse triangle? Student: yes. (after painting) Student 1: I drew a triangle like this: it is different from the three types above. 2: second and above is the same, an obtuse angle and the two angle. Student 3: I painted it. Its different from the three types above. Sheng 4: I think it is the same as the first one. The upper corner is right angle (and verified with a triangle ruler), and there is also a right angle and two sharp angles. Teacher: is there any more? After waiting for a while, no one came to the stage to communicate with each other Teacher: we can see that the triangle is the only characteristic of the three. Then what are the names of the three triangles? Please read your books and study by yourself. Student: I know there is a right angle triangle is a right triangle, a triangle is obtuse angle is an obtuse triangle, the three corners is an acute triangle called acute triangle. (according to the answer of the student teacher writing on the blackboard a right angled triangle, obtuse triangle, triangle) Analysis: in the process of understanding and obtuse triangle acute triangle, I let the students draw a triangle, and then observe the characteristics of the three angles, th