《义务教育数学课程标准(修订版)》将“数感”列为十大概念核心之首,因此,教学中培养和发展学生的数感是数学教育的重要任务之一,而“数的认识”教学就承载了培养学生数感的重要任务.江苏省特级教师苏瑜老师执教的一年级下册“认数11~20”这一课,让学生在操作、观察、估测、交流和反思等活动中逐步加深对数的体验和感悟,有效促进了学生数感的形成与发展.现择录几个教学片段以飨同仁.【片段一】“做”中感知,建立数感 “Compulsory Education Curriculum Standards (Revised Edition)” will be “number sense” as the top ten core concepts, therefore, training and development of students in teaching sense of the number of math education is one of the important tasks, and “ Number of understanding ”teaching carries the important task of cultivating students sense of number.Jiangsu province super-teacher Su Yu coached the first grade under the book “ recognized 11 ~ 20 ”this class, so that students in the operation, observation, Evaluation, exchange and reflection and other activities to gradually deepen the experience of logarithm and perception, effectively promote the formation and development of the number of sense of the number of students. Perception, the establishment of a sense of number