教师应怎样做好课堂演示实验

2025-02-25 09:10:24
推荐回答(1个)
回答1:

教师应怎样做好课堂演示实验
一、课前准备要充分
演示实验作为一种教学手段,是教师备课的重要内容,需要教师认真研究和准备。有的教师 轻视课前演示实验的准备工作, 结果造成演示失败或出现意想不到的情况, 以致在课堂上手 忙脚乱,“强行”让学生接受结论,教学效果很不理想。
二、操作要规范
操作规范是指教师在使用仪器、连接和装配仪器及演示现象时动作要准确、标准。例如 在使用托盘天平时,取用砝码、移动游码必须用镊子而不能用手;点燃酒精灯后火柴签不能 随手扔在地上, 要放在专门的废物杯中; 电路的连接应先接线路后接电源, 拆卸时先断电源, 后拆线路; 导线两端接头不是钩、 叉时要注意导线在接线柱上的绕向应同螺母旋紧的方向一 致等。 教师的一举一动都会给学生留下深刻的印象, 起到潜移默化的作用。 教师的规范操作, 不仅是实验成功的前提,而且会使学生养成严谨求实的良好实验习惯。
三、实验用语要准确
教师在介绍实验仪器、阐述实验过程和总结实验结论时,语言必须准确不含糊。有的教 师在进行演示实验时不注意语言的准确表达,对学生正确认识仪器、形成概念、掌握定律就 会产生不良的影响。
四、要让学生参与配合
演示实验不能先由教师做给学生看,再讲给学生听,使演示与讲解脱节。这种作法忽视 了学生学习的主动性,把学生当作被动接收的“仓库”,完全没有发挥出演示实验的作用,是 不可取的。教师要在演示的同时引导学生观察,不断启发提问,让学生分析、讨论,充分调 动学生学习的积极性,使实验结论合情合理地被推导出来。还可以让学生参与做实验,如让 学生上前来读数或动一动手。
五、可见度要高
演示实验不仅要现象清楚,而且还要面向全体学生。教师要想方设法增大演示实验的可见 度。投影放大、机械放大、自制可见度大的仪器进行演示等都是常用的方法。

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