That is, teachers assign preview tasks, and students preview with clear preview tasks. Let students preview with tasks, which can be targeted and targeted. For example, when I teach "the comparison of decimal size and decimal nature", I let students preview in the form of questions. These questions are as follows:

1. Which part should I look at first when comparing the sizes of two decimals? If the integer parts are the same, how to compare the sizes of two decimals?

2. What is the essence of decimals?

3. What is the simplification of decimals?

This method requires teachers to set high standards and strict requirements for themselves, carefully study relevant learning contents, and put forward preview tasks that are both valuable and attractive and can arouse students' strong interest in learning and exploration. When teachers assign tasks, they can take the form of tables or questions for students to preview. When arranging preview tasks, we should pay attention to moderate difficulty, inducement and interest, clear preview requirements and strong operability.

Second, the note preview method

If the preview content is about the teaching of concepts, formulas and theorems, you can use this preview method. At first, students can circle the book or make simple comments. After reading the textbook, they can write down their own understanding, experience or original opinions in the blank space of the book. Secondly, students can take notes, that is, after previewing, they can extract key concepts and sentences. Deepen your memory and understanding of important knowledge in the notebook, and simply write down the doubts and puzzles in the preview process, and also record your gains in the preview.

For example, when I was teaching circular decimals, I asked students to preview new lessons by taking notes. Let them first find out what circulating decimals are in the textbook through preview; What is infinite decimal and what is finite decimal; Then ask them to write down their understanding or non-understanding of these three concepts. During the communication before the new class the next day, I found that some students wrote in the notebook: "2. The number 1 756756/... is not cyclic, so is this number a cyclic decimal?" Another student wrote: "I think if an ellipsis is added after a number, then the number must be an infinite decimal." In short, writing down experiences or problems is beneficial to the acceptance of new knowledge.

However, at the beginning of this preview method, teachers should spare some class hours with their classmates to give detailed guidance on requirements, steps, methods and formats, and then let students preview and take notes independently. In addition, for students with good foundation, they can also be asked to make reflective preview notes with high thinking content.

Third, self-questioning inquiry method

Problems are the source of learning, and learning without problems is like a stagnant pool, so the cultivation of problem consciousness is particularly important. In the preview, students will inevitably have questions that they don't understand. We can train students to write down the questions they don't understand, so that when the teacher explains the next day, students can take the questions to class, and the class will be targeted, and the efficiency of class will naturally improve.

This method is similar to the previous method, but not exactly the same. Asking yourself is to record the questions that you can't figure out when you preview. For example, when teaching "Angle Measurement", I ask students to preview by asking themselves questions. The next day, I collected the students' confused questions, including several kinds:

1, the number on the protractor has two circles. what do you think?

2. Some corners are not drawn correctly. How to measure their degrees?

3. What if the corner edge is too short to reach the scale line of the protractor?

4. How to align the protractor with the angle?

To tell the truth, I felt that some students' questions were very simple, so I didn't have to talk about them or pass by. But when I saw their questions in the preview, I felt that my understanding of my classmates was still so incomplete. With these problems, teachers can find students' "pulse" in class, students can have a purpose in class, and classroom efficiency will be improved a lot.

Fourth, review old knowledge and learn new preview methods.

This is a preview of the connection between old and new knowledge. In the process of preview, on the one hand, we get to know the new knowledge, summarize the key points of the new knowledge and find out the difficulties, on the other hand, we review, consolidate and cram the old knowledge associated with the new knowledge. When it is required to preview new content, it should be connected with the old knowledge that has been learned, so as to "review the old knowledge and learn the new", contact the old knowledge, learn the new knowledge, and make the knowledge systematic.

When teaching "Decimal Multiplying Integer", I ask students to recall the knowledge point "What changes will be caused by the movement of decimal point" in the preview process, and then let them preview the new lesson content on this basis. This can systematize knowledge, reduce the difficulty of new knowledge and make students accept new knowledge easily.

Fifth, try to practice the preview method.

For relatively simple learning content, such as computing courses, students often can't ask questions after previewing and feel that they know everything, but there are many loopholes in doing it. Design a "self-test" column in the syllabus to guide students to choose their favorite topics and try to practice in preview. For example, when learning "addition and subtraction of decimals", because the knowledge of this lesson is relatively simple, most students can understand it after reading the textbook, so I ask them to do the second problem of independent exercises-calculation and checking calculation after previewing. Results There were some problems in the process of doing the problem: 10-0.8 = 0.2, 26.8 1+5.29 = 3 1 and so on. When they know that the answer is wrong through inspection, they will look for the answer from the textbook again and then practice.

By trying to practice, students' preview effect can be tested, which is an indispensable process of math preview. Mathematics is different from other disciplines, and it needs mathematical knowledge to solve problems. Students have initially understood and mastered new mathematics knowledge through their own efforts. Let them test the effect of preview by doing exercises or solving simple problems. It can not only make students reflect on the loopholes in the preview process, but also let teachers find the problems of students concentrating on learning new knowledge, thus grasping the important and difficult points in classroom teaching.

Six, hands-on preview method

For highly operational knowledge such as formula derivation, students are required to practice by themselves in the preview process, and experience and feel new knowledge through activities such as cutting, spelling, folding, moving, swinging, drawing, measuring, observing and comparing. Because there is hands-on content in the class, it is natural to be familiar with the teaching materials, understand the tools and materials needed in the operation process, and make preparations before class. Only when students have experienced the process of forming mathematical knowledge can they know why.

For example, when teaching the area of a parallelogram, I ask students to do this in the preview: first, know what a parallelogram is by reading the textbook, then draw a parallelogram and cut it out, then turn it into a rectangle (you can change it according to the method in class or find your own way), and finally measure the length and width of the rectangle, find out the area of the rectangle, and think about how to calculate the area of the parallelogram. In this way, most students can understand the area formula of parallelogram through their hands-on operation.

This is my old collection. I hope it can help you.