Joint Teaching Research Activity on Cosine Theorem Promotes Math Teaching

On May 23, a joint teaching research activity focusing on high school math classroom teaching was held at Longmen Middle School in Nanchong, Sichuan Province. Teachers from Nanchong Senior High School Math Master Teacher Studio, Wei Yang Master Teacher Studio of Senior High School Math in Nanchong Senior High School, Han Yongqiang Master Teacher Studio of Senior High School Math in Nanchong Senior High School, and the math group of Longmen Middle School gathered together. Centering around the teaching topic "Cosine Theorem" and taking "teaching the same lesson with different methods" as the research direction, they carried out in-depth discussions. Zhang Limei, the executive principal, attended the whole teaching observation activity. Tang Bing, the deputy secretary of the Party committee, and Zhang Hongbo, the vice principal, participated in the teaching evaluation activity.

Classroom Teaching: Presenting the Beauty of Math from Multiple Dimensions

Regarding the teaching of "Cosine Theorem" through different methods, Xie Jianmei, a teacher from Longmen Middle School, gave an excellent demonstration class first. She skillfully conformed to the law of students' knowledge acquisition. Starting from what students had learned in junior high school to arouse associations, and using a series of progressively advanced questions to guide students' thinking, she smoothly transitioned to the proof process using the vector method. This way of deriving from the known to the unknown enabled students to build new cognition on their existing knowledge systems, demonstrating her solid teaching skills and accurate grasp of students' learning situations.

Teacher He Jin from the master teacher studio presented a "feast of thinking" for math proofs through multi-method exploration. He innovatively adopted three different proof methods: the vector method, the coordinate method, and the geometric method, and analyzed the essence of the theorem from multiple dimensions. In class, Teacher He guided students to compare the logical paths of different methods, allowing students to appreciate the versatility and flexibility of math proofs and effectively expanding students' mathematical thinking dimensions.

Teacher Huang Rongyun from the master teacher studio brought a lecture-sharing on "Cosine Theorem". She elaborated in detail on the design methods and teaching concepts of this lesson, especially the handling methods of the proof of the cosine theorem. From textbook analysis, student situation positioning to teaching link design, she gave a comprehensive interpretation. Her clear teaching ideas and innovative teaching designs provided extremely valuable teaching paradigms for the teachers present.

Teaching Evaluation and Discussion: Reaching Consensus through Idea Collisions

After the classroom teaching demonstrations, an excellent teaching evaluation activity was carried out.

Tang Bing, the deputy secretary of the Party committee of the school, delivered a welcome speech before the teaching evaluation activity. He expressed the hope that through the learning and communication platform of joint teaching research, in-depth interactions between schools and teachers could be promoted to achieve common research, common progress, and mutual learning in teaching.

The teaching evaluation activity consisted of self-evaluations by the teaching demonstration teachers and evaluations by experts. First, the teaching demonstration teachers conducted self-evaluations, sharing the original intentions of their teaching designs and their insights into classroom implementation. After the self-evaluations, Yin Huaqian, a member of the city's master teacher studio, and Liao Haiquan, a teacher from the math group of Longmen Middle School, respectively evaluated the classes. They highly praised Teacher Xie Jianmei for closely following the law of students' cognitive development in her teaching process and having a natural and smooth knowledge connection. They admired Teacher He Jin's teaching mode of multi-method proofs, believing that it greatly stimulated students' enthusiasm for exploration. They also fully affirmed the teaching concepts and design logics reflected in Teacher Huang Rongyun's lecture.

Master Teacher Summaries: Pointing out Directions for Teaching Improvement

Wei Yang, the host of Nanchong Senior High School Math Master Teacher Studio and Wei Yang Master Teacher Studio of Senior High School Math in Nanchong Senior High School, and Han Yongqiang, the host of Han Yongqiang Master Teacher Studio of Senior High School Math in Nanchong Senior High School, gave summary speeches. From the perspectives of curriculum standard requirements and core literacy cultivation, Teacher Han Yongqiang systematically sorted out the highlights and areas for improvement of the three classes, emphasizing that math teaching should focus on the knowledge generation process and the guidance of thinking methods. Teacher Wei Yang, combining his own teaching experience, put forward in-depth suggestions for deepening the "teaching the same lesson with different methods" teaching research model, encouraging teachers to not only pay attention to common rules in teaching but also highlight their individual characteristics.

In-depth Communication: Jointly Discussing Educational Development

During the teaching evaluation activity, Vice Principal Zhang Hongbo had in-depth exchanges with experts from the master teacher studio. The two sides discussed issues such as the reform direction of high school math courses, the improvement of classroom teaching efficiency, and the professional development paths of teachers. Through idea collisions, they reached a consensus on education and teaching, laying a solid foundation for subsequent in-depth cooperation.

This joint teaching research activity built a platform for mutual observation, learning, communication, and discussion through the complete teaching research chain of "teaching - lecture-sharing - teaching evaluation". The collisions of different teaching styles and the displays of different teaching methods enabled teachers to benefit a lot from comparisons, reflections, and discussions. The school will continue to promote regular joint teaching research with the master teacher studio and jointly strive to write a new chapter in math education.