一、在学生已有的认知基础上创设问题情境学生的学习是以一切现有的认知发展水平为出发点,所以知识的引入只有在与学生的认知水平相适才能促进学生的主动建构。简单地说,就是新知识的学习总是在原有的基础上进行的。因此,在教学新的内容时,教师应注意从学生已有的知识背景出发,提供丰富的感性材料,展现知识产生发展的实际背景,设法激活学生已有的数学知识经验和生活经验,引导和 First, based on the existing cognition of students to create a problem situation Students learn is based on all existing levels of cognitive development as a starting point, so the introduction of knowledge and students only in the cognitive level to adapt to promote students’ initiative to construct . In short, the learning of new knowledge is always based on the original. Therefore, when teaching new contents, teachers should pay attention to providing rich and perceptual material from the students ’existing knowledge background, showing the actual background of knowledge development, trying to activate students’ experience of mathematical knowledge and life experiences, and guiding