当我们的教学越来越精致的时候,要求学生的画图也越来越严谨。近些年,草图似乎被排挤出探究与训练的大门。然而,画草图,会画草图,画好草图,对于学生建立正确的空间观念,纠正错误的空间观念,学习几何学,有着十分重要的意义和作用。我们经常遇到这样的情况,有些学生,使用标准工具,按照标准程序,画出的垂直不垂直,画出的平行不平行,他们却不自知,没觉得不平行,也没觉得不垂直,甚至不如偷懒学生用直尺画得准确。为什么工具 As our teaching is getting more and more refined, the drawing of students is also required to be more and more rigorous. In recent years, sketches seem to be squeezed out of the door of inquiry and training. However, drawing sketches, drawing sketches and drawing sketches have very important meanings and functions for students to establish correct concepts of space, correct wrong spatial concepts and learn geometry. We often encounter such a situation. Some students, using standard tools, according to standard procedures, draw the vertical is not vertical, drawn parallel is not parallel, they do not know, did not feel not parallel, did not feel not vertical, Not even as lazy students draw the ruler accurately. Why the tool