学生在掌握基础知识、基本技能和发展能力的过程中,需要通过练习。课堂练习具有三种功能,即:知识的内化(学生对知识的识记和保持);学习的矮正;教学的调节。然而应该在课堂上让学生练习什么,用什么方法练,什么时候练习效果较佳等方面都需要继续研究。一、课堂练习的内容初中化学内容多,需要精选。选择课堂练习内容有两个原则:一是要根据中学化学教学大纲里的目的和要求,选择哪些最主要的,有代表性的,在初中阶段必须掌握的内容;二是必须根据 Students need to practice through the process of mastering basic knowledge, basic skills, and developing abilities. Classroom exercises have three functions, namely: the internalization of knowledge (students’ knowledge and retention of knowledge); the dwarfing of learning; and the adjustment of teaching. However, what students should practice in the classroom, what methods to use, and when to practice better, etc., need to continue to study. First, the content of the classroom exercise The chemistry content of junior high school needs to be selected. There are two principles for choosing classroom exercises: First, according to the objectives and requirements in the chemistry syllabus for middle schools, what are the most important and representative ones that must be mastered at the junior high school level; second, they must be based on