沉浮是生活中常见的现象,其间蕴含着深刻的科学道理。选取《沉浮的奥秘》这一内容,不仅是为了使学生逐步学会自主地“搞科学”,而且也渗透着事物发展、变化的观点。在设计本课时,教学的着力点由文化知识传承转向了激发创新,力求体现以下几点: 一、实验材料的动态性。本课选取的实验材料是一次 Ups and downs is a common phenomenon in life, during which implies a profound scientific truth. The selection of the mystery of ups and downs not only aims to enable students to gradually learn to autonomously “engage in science,” but also permeates the viewpoint of the development and change of things. In the design of this lesson, the focus of teaching shifted from the cultural heritage to stimulate innovation, and strive to reflect the following: First, the dynamic experimental materials. The experimental material selected in this lesson is once