Yu Yi, a famous special-grade teacher, once said: "The first hammer in the class should knock on the students' hearts, arouse the sparks of their thinking, or attract the students as firmly as a magnet. "Whether the beginning of a class can quickly grasp the students' hearts is very important for the success or failure of a class. Therefore, teachers should design the first few minutes of class according to actual needs, arouse students' enthusiasm, produce the effect of "interesting class for students", and let students enter the classroom easily and naturally. First, make good use of the situation to introduce modern psychology: "All human behaviors are caused by motivation." Stimulating students' participation motivation is the premise of guiding students to learn actively. Therefore, when introducing new courses, we should try our best to create situations for students, stimulate their desire for learning and urge them to study actively. It goes without saying that students can enter the classroom under the demand of "I want to learn". For example, when teaching "circular decimals", I first tell the students a short and humorous story: "Once upon a time, there was a mountain, a temple on the mountain, and there was an old monk in the temple. He told the young monk that there used to be a mountain, a temple on the mountain and an old monk in the temple. He said to the young monk, "Once upon a time …" Hearing this, the students began to be restless, and some students began to shout, "This story will never be finished. Don't waste time." I immediately asked, "Why can't this story go on forever?" "Because this story always repeats those words." "Very well said. In the mysterious kingdom of mathematics, there is such a decimal, and the numbers in the decimal part will appear repeatedly like a few words in this story. Do you want to unveil its mystery? " Such a scene makes students suddenly enter a learning state with needs, which not only stimulates students' interest, but also enables students to initially perceive the meanings of keywords in concepts such as infinity and repetition in a pleasant and harmonious atmosphere, laying a good foundation for the formation of concepts and the mastery of new knowledge. Second, the problem of clever design is artistic labor. Teachers skillfully ask all kinds of heuristic questions with vivid language and appropriate gestures and actions, which is very good for attracting students' attention and improving the guiding effect of the new curriculum. Therefore, in teaching, teachers should pay great attention to their own mathematics language, skillfully design questions when guiding people to acquire new knowledge, induce students with questions, stimulate students' interest in learning, make students have a strong desire to learn, and naturally enter the learning state in the process of "asking and answering", thus improving the classroom efficiency of mathematics classes. For example, students tend to confuse the concepts of "area" and "volume", especially the understanding of "volume" is vague. Teachers can introduce the concept of "volume" by asking questions: first, take two identical glasses and fill them with the same amount of water, so that students can observe that the water levels of the two glasses are the same, and then put a stone in one of the glasses and ask, "What do you see? What else did you find? " At this time, the students found that the level of the cup had risen. The teacher asked, "Does this mean that the water in this cup has increased?" The students immediately denied it. "Why is that?" The student replied, "Teacher, the stone you put takes up space and the water is squeezed up." Students have entered the state of establishing the conceptual model of "volume". The teacher took out a bigger stone and put it in another cup, and asked, "What did you find this time?" The students found that the level of the second cup was higher than that of the first cup. The teacher asked again, "Do you know why?" The student replied positively, "The second stone is bigger than the first one, so it takes up more space." After this introduction, the teacher revealed that "the size of the space occupied by an object is called the volume of this object." At this time, students have entered the classroom, and the understanding of volume will naturally follow. Third, with the help of "play", primary school students are naturally active, and it is the nature of every primary school student to love to play. Therefore, as a teacher, we should make full use of this characteristic of primary school students and design some games or practical operations related to the teaching content that require students' participation, so that students can "play" for a few minutes. Make use of students' curiosity and activeness. Let them enter the classroom unconsciously in "playing". For example, when teaching lateral area of cylinders. First, let the students take out the prepared cylinder, then find a piece of paper to cover one side of it and see what kind of paper can just cover one side of it. The students' emotions are unprecedented in the process of "playing". After practical operation, we can not only quickly find that the side of the cylinder is a rectangle, but also be interested in finding the connection between this rectangle and the side of the cylinder. At this time, the purpose of this class is close at hand. Fourth, introducing selected old knowledge, reviewing old knowledge and introducing new lessons is the most commonly used method of starting classes. Pupils' mastery of knowledge is often not strong enough, so when teaching the knowledge related to the last lesson, it is advisable to select the content that is helpful to the new lesson, and then match it with a well-designed training plan, so that students can naturally transition from old knowledge to new knowledge. For example, when teaching students to draw a circle, first review the basic knowledge of the circle, so that students can deeply understand the knowledge that all radii of the circle are the same, and then ask: "Who can draw a qualified circle without compasses?" Students will immediately have the impulse to draw a circle. In this way, the students not only consolidated the old knowledge, but also thought about how to draw a qualified circle without compasses according to the learned knowledge, which not only reviewed the old knowledge, successfully guided the classroom, but also cultivated the students' thinking ability.