In daily teaching, it is often twice the result with half the effort to let students use a variety of senses, personally participate in the actual operation, observation, cooperation and communication in teaching, and personally touch and have a look (that is, what is visible is worth seeing), which is also the concept advocated by the new curriculum. For example, when I was teaching the teaching design of the derivation process of the triangle area calculation formula in the ninth volume of primary school mathematics, I did this:

First of all, the teaching objectives of this class are determined as follows: 1. On the basis of understanding, master the calculation formula of triangle area and calculate the area of triangle correctly; 2. Through the operation, observation, comparison and development of the concept of space, students can understand the application of transformation thinking method in the study of triangle area, and cultivate their ability to analyze, synthesize, abstract, summarize and apply transformation method to solve practical problems; 3. Cultivate innovative consciousness and cooperative spirit. Teaching emphasis and difficulty: the derivation process of triangle area calculation formula. Teaching preparation: Demonstrator for deducing triangle area formula, two identical right triangles, two identical acute triangles and two identical obtuse triangles.

Secondly, in the teaching process, the relationship between presupposition and generation is handled as follows: teaching process: (divided into three steps)

Let the students observe their red scarves. What shape is it? How to calculate its area? Today we are going to learn the calculation method of triangle area. Blackboard writing: the area of a triangle

Second, teaching implementation: 1, recalling the derivation process of parallelogram area calculation formula (personal speech). 2. Teachers organize, guide, participate and cooperate to complete the derivation process of triangle area calculation formula (completed by group cooperation): (1) Make a parallelogram with two identical acute triangles; (2) Using two identical obtuse triangles to form a parallelogram; (3) Using two identical right-angled triangles to form a parallelogram; This allows students to explain after actual operation, observation, communication, analysis and discovery, and draw a conclusion: S = AH ÷ 2 3. Doubt: Can a triangle be transformed into a learned figure, and thus the formula for calculating the triangle area can be deduced. After thinking, operating and communicating, students find (knowledge is automatically generated), but they don't know what these methods are called (digging and filling method, folding method), and they quickly understand and master them under the guidance of teachers. Students learn examples by themselves and teachers help them. 5, class summary (individual speech, supplement).

Third, classroom exercises: 1, students independently complete the "what to do" and related exercises in the textbook, and the teacher provides individual counseling and help in due course. 2. Teachers show pre-designed supplementary questions (with certain gradients and illustrations), patrol and participate in students' completion.