Ten MINUS nine is a subtraction course that abdicates within 20 years, and it is the basis of learning how to subtract several from ten, so it is very important to learn it well, but the calculation course is boring and students are not interested, especially freshmen. In teaching design, I create meaningful life situations that students are interested in, integrate computing teaching into specific situations, and encourage students to actively participate in learning. Through teaching, the reflection on this lesson is as follows:

First of all, students' enthusiasm for learning is very high by integrating computing teaching into real life situations that students are interested in.

? The whole class revolves around situations that students are interested in. According to the information, students can easily raise and solve math problems and constantly experience the joy of success. Students are very enthusiastic about learning.

Second, let students experience the formation process of knowledge in independent exploration and cooperation and exchange, so that students can better understand and master new knowledge.

? When learning new knowledge, I organize students to explore independently. Then let students cooperate and communicate on the basis of independent exploration, let students explore the formation process of new knowledge, and understand how to solve problems through "breaking ten methods or leveling ten methods", so that organizing teaching can not only better implement the teaching objectives of this class, but also fully reflect that students are the masters of learning, and at the same time cultivate students' communication ability and cooperation consciousness.

Thirdly, respecting differences and embodying the diversity of algorithms can enhance students' confidence in learning mathematics.

Students are exploring 13-9=? Due to the differences among students, there are many calculation methods: ① Count the remaining peaches and calculate13-9 = 4; ② Want to add or subtract: 9+4= 13,13-9 = 4; ③ Ten-break method: 10-9= 1, 1+3 = 4,13-9 = 4; ④ Continuous reduction: 13-3-6=4,13-9 = 4; I respect differences, show each method and affirm it one by one, so that different students can experience the fun of exploring success in mathematics learning activities and realize the different development of students at different levels.

Fourth, what needs to be improved is to strengthen the guidance of students.

After 13-9 is displayed, I ask my deskmates to discuss with each other, circle them and count them by drawing sticks to see how 13-9 works. In the course of traveling, I found that many children can count, but they don't know how to put a stick. And I didn't give the children some guidance, just let them talk at the same table. Seeing that some children can't speak, they are eager to ask other children to talk about their own algorithms, resulting in some children with poor foundations having no time to think at all. In fact, on the surface, it seems that children are exploring independently, but students don't give help when they encounter difficulties. This kind of autonomous learning has little effect. In the future, we need to further study the effectiveness of students' autonomous learning.