In this class, Mr. Bu discusses the teaching design of this class from the perspective of mathematics module. Mathematical module refers to the integrated block of some mathematical knowledge and skills, which is the combined component in mathematical problems, the thinking method to solve some mathematical problems, and the basic experience and method for people to identify specific modules. Mathematics module includes knowledge module, skill module, method module and experience module.
1. Discusses the judgment method of rectangle. Teacher Bu uses the method module: The methods to judge a quadrilateral as a special quadrilateral mainly include: discussing the judgment conditions from the element of "angle"; Explore the judgment conditions from the element of "edge"; Discussion on judging conditions from "diagonal" factors. The above method is a static view of judgment. If we understand from the dynamic judgment view, we can strengthen the conditions from the original basic graphics and get the judgment conditions, that is, we can get the rectangular judgment conditions by strengthening the parallelogram conditions.
2. For the understanding of judging methods, Mr. Bu gave two empirical models: one is how to judge rectangles based on parallelograms; The other is how to judge the rectangle on the basis of arbitrary quadrilateral.
3. With regard to how to use judgment to solve practical problems, Mr. Bu described the skill module: the skills of variation and change of problems, mathematicization and modeling.
Usually after judging the rectangle, the teacher will ask the students a question: how to check whether the woodworker's door frame is rectangular with a ruler, and talk about your thoughts. Generally speaking, there are three methods:
Method 1: First, check whether the opposite sides of the door frame are equal, and then check whether one of the angles is a right angle.
Method 2: First, check whether the opposite sides of the door frame are separated and equal, and then check whether the distance between the two pairs of diagonals, that is, whether the lengths of the diagonals are equal.
Method 3: Check whether the three corners of the door frame are right angles.
The purpose of studying this problem is mainly to apply the judgment method to practical problems, cultivate students' mathematical ability, accumulate mathematical experience, and consolidate how to judge a figure as a rectangle again.
4. Use judgment to solve mathematical problems. Here, Mr. Bu mainly explains the refinement and summary of the knowledge module.
In teaching, we should start from students' existing knowledge reserves and cognitive basis, and bind students tightly to the dimension of mathematical thinking activity through the teaching of module recognition. This can not only effectively train students' mathematical thinking, but also accumulate students' basic experience in mathematical activities, provide an effective activity carrier, and lay a good foundation and provide guarantee for subsequent learning.
It is worth noting that as a teacher, we should pay attention to guiding students to dig and organize math modules. At the same time, we should know that mathematics module is not the final product formed on a certain knowledge point, but develops and perfects with the deepening of students' knowledge, and it has a growing process. We should seek organically in teaching. What is this fast, skill module, method module, experience module? It is a new way for students to experience in solving problems. The role of mathematics module, to feel the charm of mathematics module.