笔者在观课过程中发现无论是在初中平常的教学课堂,还是一些大型的全国初中比赛课,都有一个现象:在重力、摩擦力、杠杆、压强、液体的压强、大气压强、流体压强与流速的关系、浮力、浮力的应用、功等内容的教学过程中,较少老师自己或引导学生画出物体的受力示意图,并教会学生如何利用力的示意图分析问题,解决问题。如流体压强与流速这节课,不少老师在课堂上做了大量的实验,有的课堂甚至一节 In the process of observation, the author found that there is a phenomenon in the common middle class teaching class or some large-scale junior middle school competitions in China. Gravity, friction, leverage, pressure, liquid pressure, barometric pressure, fluid pressure and The relationship between the flow rate, buoyancy, buoyancy, work and other content of the teaching process, fewer teachers or guide students to draw the object stress diagram, and teach students how to use the power of the schematic analysis and problem solving. Such as fluid pressure and flow rate of this class, many teachers in the classroom to do a lot of experiments, and some even a section of the classroom