随着我国基础教育的培养目标逐渐转向高阶思维能力的培养，项目学习这种教学方法近些年在我国逐渐受到越来越多的关注，《义务教育数学课程标准（2022年版）》中也提出初中阶段可以采用跨学科项目式学习的方式开展综合实践活动课程。很多研究都对项目学习在学生高阶思维能力培养方面的教学效果进行了测量和评估，研究结果表明项目学习对学生的批判性思维、创造性思维和问题解决能力等都有积极的影响，但是较少有研究从具体的教学行为特征角度进行研究，本文则从指向高阶思维的课堂对话特征这一相对微观的角度对从初中数学项目学习课堂进行深入研究。

本研究数据取于北京市某区“项目学习区域整体改革”项目中一位种子教师实施的两个项目，均为高质量专家级项目学习课堂。将项目学习课堂教学录像转录成文本，根据基于数学思维进阶的分析框架，对教师和学生的课堂对话进行编码，分析解释涉及各类高阶思维编码发生的频率和位置，并进一步分析不同环节中指向高阶思维的课堂对话结构，通过对两个项目案例客观深入的分析，来探究项目学习课堂互动方面高阶思维相关的话语特征，为一线教师项目学习的具体实施提供帮助。

基于此，本研究得出以下结论：（1）回应建构类课堂话语占比最高，且显著高于传统课堂；（2）解释论证、举例阐释和推断猜想类话语主要由学生主动发起，而评价分析、建立模型和归纳总结等类话语主要由教师发起；（3）不同环节的问题提出教学片段中教师的提问和反馈所涉及的对话种类各不相同。在此基础上，对教师实施项目学习提出如下建议：（1）在项目学习课堂全过程中从不同角度引导学生进行拓展，并在核心知识任务方面进行深化追问；（2）教师可以通过解释论证、建立模型和归纳总结类话语有效协助学生成为项目学习的主体；（3）在引导学生问题提出和解决的多轮循环过程中培养学生的高阶思维。

With the training goals of basic education in China towards the cultivation of high-order thinking abilities, project-based learning as a teaching method has gradually received more and more attention in China in recent years. The " Curriculum standards for mathematics in nine-year compulsory education (2022 version) " also proposes that interdisciplinary project-based learning can be used to carry out comprehensive practical activity courses in junior high school. Many studies have measured and evaluated the teaching effect of project-based learning on the cultivation of students' high-order thinking abilities. The research results show that project-based learning has a positive impact on students' critical thinking, creative thinking and problem-solving ability. However, few studies have been designed from the perspective of specific teaching behavior characteristics. This article studies the project-based learning mathematics classrooms of junior high school from a relatively micro perspective of classroom dialogue characteristics pointing to high-order thinking.

This study takes data from two projects implemented by a seed teacher in the "Overall Reform of Project-based Learning in Regions" project in a certain district of Beijing. Both of projects are high-quality and expert-level project-based learning classrooms. This study transcripts project-based learning teaching videos into text, codes classroom dialogue between teachers and students using an analytical framework which is based on advanced mathematical thinking, analyzes and explains the frequency and location of various high-order thinking encoding. And then, this study analyzes the classroom dialogue structure pointing to high-order thinking in different stages. Through objective and in-depth analysis of two project cases, this study explores the discourse characteristics related to high-order thinking in project-based learning classroom interaction, and provide assistance for the specific implementation of project-based learning by frontline teachers.

Based on this, this study draws the following conclusions: (1) The proportion of construction classroom discourse is the highest and significantly higher than that of traditional classrooms; (2) The discourse of explanation and argumentation, illustration with examples, and inferential conjecture is mainly initiated by students, while the discourse of evaluation and analysis, model building, and induction and summary is mainly initiated by teachers; (3) The types of teacher's questioning and feedback dialogues in different teaching segments are different. Thus, the following suggestions are proposed for teachers to implement project-based learning: (1) Guide students to extend from different perspectives throughout the project-based learning classroom, and deepen questioning in terms of core knowledge tasks; (2) Teachers can effectively assist students to become the subject of project-based learning by explaining and demonstrating, establishing models, and summarizing discourse; (3) Cultivate students' high-order thinking through multiple rounds of guiding them to raise and solve problems.