加强对比 领悟内涵

• 作 者: 严政建
• 机 构: 浙江省杭州市文渊小学,
• 出 处: 吉林教育
• 发表日期: 2013年20期
• 关键词: 空间观念 教学片断 小观 动态处理 直接观察法 对比教学 实验活动 严政 示图 认知冲突

一、通过对比,让体积概念“标准”起来师:出示图1图2师:你觉得图1与图2哪个体积比较大?(见图1、2)。生:我觉得图1体积大。师:大了多少呢?生1:图1比图2大了一个小正方体。生2:图1是4个小正方体,图2有3个小正方体。生3:找出同样大小的物体的个数,相差几个就可

First, by contrast, let the concept of volume “standard ” up: to produce Figure 1 Figure 2 Division: What do you think of Figure 1 and Figure 2 which volume is relatively large (see Figure 1,2). Health: I think Figure 1 is bulky. Teacher: How much is big? Health 1: Figure 1 is larger than Figure 2 a small cube. Students 2: Figure 1 is a 4 small cube, Figure 2 has 3 small cubes. Students 3: Find the same number of objects in the same size, a few can be