2006年4月4日,笔者参加了上海市青年教师教学优质课评比,获得一等奖.上课内容为“等差数列的前n项和公式(一)”.本文围绕着这节课的设计、试教及修改的全过程,谈谈本人在二期课改背景下对课堂教学设计的一点体会.等差数列是高中数学研究的两个基本数列之一.等差数列的前n项和公 On April 4, 2006, the author participated in the Shanghai Young Teachers’ Teaching Quality Assessment and won the first prize. The content of the class is “The first n items of the arithmetic progression and formula (1)”. This article revolves around the design of this lesson. The whole process of the trial teaching and modification, talk about my experience in class teaching design in the context of the second period curriculum reform. The arithmetic progression is one of the two basic sequences of mathematics research in high school. The first n items of the arithmetic progression are public