Let's talk about Mr. Huang's practice class first. Generally speaking, the design of this class can be described as exquisite. A piece of wood bounced the whole class and the students liked it very much. Here's the process. At the beginning of the class, Mr. Huang showed a picture of wood that the students were familiar with and asked the students to associate it. The children connected it with the side area of the cylinder they learned, and painted it with a layer of paint to calculate the surface area. Some students thought of cutting it into a cone with equal bottom and equal height, and asked to cut off part of the volume or the rest. Some children even mentioned that you can hollow out the middle of the wood and turn it into a hollow wooden tube. Teacher Huang put forward keywords such as "cut", "dig", "brush" and "cut" from the Children's Association. Then let the children choose a topic and try to make up a valuable math problem, only counting it. After the children selected the theme in groups, they began to think independently and finished their creation. Finally, the whole class shared their own designs and ideas.
In this class, every child's enthusiasm is mobilized, and they take the initiative to invest and create. Finally, after collecting and classifying the creative topics, it is found that 65% of the students chose the theme of "cutting" to create, which has high similarity. After deep thinking, we found that this class looks very lively, but each child is only exposed to one question written by himself or four questions in the group. The sharing of other groups stays at the listening level, and not all children are involved in analyzing and solving problems. How to break through this problem? I think: it is still necessary to combine the actual learning situation of children and let all children participate in the solution of practical problems. In the process of solving problems, they can feel the connection between mathematics and life, feel the effectiveness of real situations, and refine the methods to solve mathematical problems.
Of course, after this question was raised, I also thought about the difficulties, especially the design of real situations and the understanding and analysis of learning situations. But in order to promote students' real learning and not design for class, we decided to analyze the learning situation first. Students make many mistakes in the surface area of the cylinder, especially the problem of increasing the cross section after cutting. In this case, we boldly decided to focus on and deeply break through the surface area problem, find the prototype of new objects in life through two different cuts, and then combine the prototype to create problems with certain thinking value, think deeply, deepen understanding and break through difficulties through experience. Then ask students to find the actual prototype in their own lives and create it. Finally, in sharing, choose meaningful situations to answer, students' thinking is open and flexible!
Although this class still needs a lot of preparation work and thinking needs to be further improved, it is very meaningful to let students feel the real mathematics and life in their study!