新的课程标准指出 ,学生的数学学习内容应当是现实的、有意义的、富有挑战性的 ,这些内容有利于学生主动地进行观察、实验、猜测、验证、推理与交流数学活动 .有效的数学学习活动不能单纯地依赖模仿与记忆 ,动手实践、自主探索与合作交流是学生学习数学的重要方式 .这一基本理 The new curriculum standards point out that students’ mathematics learning content should be realistic, meaningful, and challenging, and these contents are conducive to students’ initiative to observe, experiment, guess, verify, reason and communicate mathematical activities. Effective mathematics Learning activities cannot simply rely on imitation and memory. Hands-on practice, independent exploration and cooperation and communication are important ways for students to learn mathematics. This basic principle