在数学教学过程中怎样引领学生构建数学模型呢?笔者结合自己的教学研究实践,以“20以内的退位减法”例5为例,以“三步走”探讨分析构建数学模型过程,与同行交流。第一步:创设教学情境,提供建模信息构建数学模型,其载体就是数学建模素材,如何选好建模素材,关系到整个建模的质量,因此,教师在搜集和整理数学建模素材时,不仅要从教材中去挖掘应用素材,更重要的是从现实生活中搜集学生能解决的数学建模素材。而数学建模素材需要教师创设 How to lead the students to construct the mathematical model in the process of mathematics teaching? The author combined his own teaching and research practice to take the example of “abort subtraction within 20” as an example to discuss the process of building a mathematical model through “three steps” , Communicate with your peers. The first step: to create a teaching situation, provide modeling information to build a mathematical model, the carrier is the mathematical modeling material, how to choose a good modeling material, related to the quality of the entire modeling, therefore, teachers collect and organize mathematical modeling material , It is not only necessary to excavate the application materials from the teaching materials, but more importantly, to collect the mathematical modeling materials that the students can solve from the real life. Mathematical modeling material needs teachers to create