在新课程改革的大背景下,课堂教学的有效性受到越来越多的关注。所谓的课堂教学的有效性就是指在一定的时间内,通过教师的教学,学生所获得的知识与能力得到有效的提高。学生知识的获得、能力的提高是衡量课堂教学有效性的唯一尺度。如果在课堂教学中,优等生觉得没收获或者收获不大,后进生觉得学 In the context of the new curriculum reform, the effectiveness of classroom teaching is receiving more and more attention. The so-called effectiveness of classroom teaching means that in a certain period of time, through the teaching of teachers, the acquired knowledge and ability of students are effectively improved. The acquisition of students’ knowledge and ability are the only measures to measure the effectiveness of classroom teaching. If in the classroom teaching, excellent students feel that there is no harvest or little gain, later students feel learning