论文部分内容阅读
在教学“三角形的内角和是180°”的时候,我按观察、实验、计算三步安排教学。一、观察。教师出示下面一组三角形,要求学生观察,先说出每个三角形的名称,再估计每个三角形的内角和,大约是多少度? (估不准不要紧)。二、实验。 1.剪拼:教师要求学生把课前准备好的一个钝角三角形,剪下它的三个内角,然后拼在一起,观察三
In teaching “the interior angle of the triangle is 180 °”, I arranged the teaching in three steps according to observation, experiment and calculation. First, observe. The teacher shows the following set of triangles, asking students to observe, first say the name of each triangle, and then estimate the internal angle of each triangle and, is about how many degrees? (Estimation does not matter does not matter). Second, the experiment. 1 cut spelling: the teacher asked the students to prepare an obtuse triangle before the class, cut its three corners, and then spell together to observe the three