“留白”原是国画创作中的一种构图方法,以白当黑,可以收到虚实相映、形神兼备,创造出无画处皆成妙境的艺术境界。艺术大师往往都是留白的高手,方寸之地亦显天地之宽。《数学课程标准》指出:教学活动是师生积极参与、交往互动、共同发展的过程。有效的教学活动是学生学与教师教的统一,学生是学习的主体,教师是学习的组织者、引导者与合作者。为了充分 “White ” was originally a kind of composition method in the traditional Chinese painting. When the white is black, you can receive both the real and the imaginary, the perfect combination of form and spirit, and create a realm of art without painting. Masters of art are often the masters of the blank, the square of the world is also wide. The “Mathematics Curriculum Standard” points out that teaching activities are the process of active participation, interaction and common development between teachers and students. Effective teaching activities are the unification of student learning and teacher education, students are the main body of learning, and teachers are the organizers, guides and collaborators of learning. To be full