2. Create situations and develop thinking.Traditional classroom teaching is generally where the teacher talks and where the students hear. Students have no room for thinking, no room for self-development, and the effectiveness of student learning is naturally reduced. The enthusiasm and initiative of students in learning often comes from a situation full of questions and problems. Teaching without problems will never leave many traces in the students' minds, and it will not arouse ripples in the students' thinking. Creating a problematic situation is a process of creating a kind of "little suspense" between the content of the textbook and the student's psychology of seeking knowledge, and introducing students into a situation related to the problem. Creating problem situations can provide students with opportunities for self-exploration, self-thinking, self-creation, self-expression, self-realization and practice. Through the creation of problem situations, students can clarify the goals of exploration and give directions to their thinking; at the same time, they have a strong desire to explore and give motivation to their thinking. For example, when teaching "the volume of a cone", I first show a cone made of plasticine and ask students to find a way to find its volume. With such a problem situation, the curiosity of the students immediately came. After thinking about it, some said that it was pinched into a cube or a cuboid, some said that it was pinched into a cylinder, and some people said that it was calculated by the drainage method. After affirming the various effective methods of the students, I raised another question: "Can students find the volume of the cone-shaped sand pile next to the teacher?" At this time, the students felt that the volume was deformed and put into the water. The method didn't work, so I realized that: cuboid, cube, and cylinder all have their own volume formulas, and then lead to thinking: Is there a formula for calculating the volume of cones? On this basis, let the students do the operation to explore the volume formula of the cone. Students learn by themselves in the situation created by the teacher. In this way, while the students' ability to explore and solve problems is continuously enhanced, they also establish a positive and healthy mathematics emotion, thereby greatly improving their learning initiative.