问题在数学学科中具有举足轻重的地位，基于问题的教学模式在数学教育领域也一直备受关注。新课程改革以来，许多数学教育工作者对高效的问题教学进行了不懈的探索和研究，其中，“问题串”通过实践研究被证明是一种有效的基于问题的教学方式。“问题串”由一连串逻辑关联在一起的问题构成，相较于单个问题而言具有独特优势，在初中数学课堂教学中发挥了积极作用，但在实际应用时，往往存在问题设置不恰当、问题设计缺少策略支持等情况。基于合理设计与应用“问题串”的需要，本文依据理论和实践基础，构建初中数学课堂教学应用“问题串”的策略，给出融入策略的教学设计并实施教学，最后测评教学实践效果和“问题串”应用策略的有效性。
本文采用理论研究和实践研究相结合的方法，通过文献分析梳理已有的“问题串”应用研究，作为本文理论基础。对部分一线初中数学教师进行问卷调查，了解当前初中数学课堂教学应用“问题串”的情况，作为策略构建的实践依据。基于理论基础和实践依据，从一堂课的课堂导入、知识探究和课堂小结三个环节构建初中数学课堂教学应用“问题串”的8个策略，分别如下：（1）设置贴近生活的问题情境，激发学生探究兴趣；（2）借助“问题串”复习旧知，搭设新旧知识衔接桥梁；（3）设计不同类型“问题串”，突破知识点；（4）对基于题目的“问题串”合理运用变式；（5）“问题串”渗透数学思想方法；（6）利用“问题串”总结归纳知识点；（7）设置课后思考题，鼓励学生自主学习；（8）根据不同学情设计不同“问题串”。
融入以上策略，以《实数的运算》和《画一次函数图象》两个课题为载体，写出教学设计并实施教学，通过访谈听课教师和学生对实践效果进行测评。测评得到：构建的“问题串”应用策略经实践检验是可行性较高的应用策略，能够有效地促进教师教学和学生思考；教师与学生对“问题串”应用策略的实践效果认可程度较高，课堂达成了教学目标，“问题串”的策略设置合理，学生在课堂上更愿意回答问题。
在教学实践过程中，通过反思运用策略指导课堂教学时出现的问题，改进“问题串”教学课堂，得到以下研究启示：（1）实际课堂具有多变性，教师应关注学生的提问和回答，给予学生充分的思考时间，根据课堂进展的实际情况和学生的知识接受情况适时调整预设好的“问题串”；（2）在课后注重反思“问题串”的具体教学行为，及时发现问题并改进；（3）教师之间可以加强交流，互相学习，分享成功的“问题串”教学经验和案例，共同打造高效的“问题串”教学课堂。

Problems have a pivotal role in mathematics, and problem-based teaching models have been of great interest in the field of mathematics education. Since the new curriculum reform, many mathematics educators have made unremitting exploration and research on effective problem-based teaching, in which "question string" have been proved to be an valid problem-based teaching method through practical research. The "question string" consists of a series of logically related questions, which has unique advantages over individual questions and plays an active role in junior high school mathematics class teaching, but in practice, there are often inappropriate question settings and lack of strategic support in question design. Based on the need for rational design and application of "question string", this paper constructs strategies for applying "question string" in junior high school mathematics class teaching based on theoretical and practical foundations, gives an instructional design and implementation of the application strategy, and finally evaluates the effectiveness of the teaching practice and the application strategy of "question string".
This paper adopts a combination of theoretical and practical research methods. The theoretical basis of this paper is the literature analysis of the existing research on the application of "question string". A questionnaire survey was conducted with some front-line junior high school mathematics teachers to understand the current situation of applying "question string" in junior high school mathematics class as a basis for strategy construction. Based on the theoretical foundation and practical basis, nine strategies for applying "question string" in junior high school mathematics class were constructed from the three aspects of class introduction, knowledge inquiry and class summary, as follows:(1) Set up question situations close to life to stimulate students' interest in learning;(2) Review old knowledge with the help of "question string" to build a bridge between old and new knowledge; (3) Design different types of "question string" to break through the knowledge points; (4) Set up variations rationally for “question string” based on mathematical problems; (5) Penetrate mathematical thinking; (6) Use "question string" to summarize knowledge points;(7) Set post-lesson reflection questions to motivate students to learn independently; (8) Design different "question string" according to different student situations. 
Incorporating the above strategies, three instructional designs were written and implemented for teaching practice, and the effectiveness of the practice was measured through interviews with teachers and students who listened to the lessons. Through the evaluation, we found that the "question string" application strategies were tested to be feasible, which could effectively promote teaching and students' enthusiasm for thinking; teachers and students recognized the effectiveness of the "question string" application strategy, and the classroom achieved the teaching objectives, the "question string" strategies were reasonable, and students were more willing to answer questions in class.
In the process of teaching practice, by reflecting on the problems that occurred when using the strategy to guide teaching and improving the "question string" teaching class, the following research insights were obtained:(1) The actual class is variable, so teachers should pay attention to students' questions and answers, give students sufficient time to think, and adjust the predetermined "question string" according to the actual progress of the class and students' knowledge acceptance at the right time; (2) Teachers should reflect on the specific teaching behaviors of the "question string" after class to identify problems and improve them in a timely manner; (3) Teachers could strengthen communication with each other, learn from each other, share successful "question string" teaching experience and cases, and create efficient "question string" class together.