Calculation is an important part of mathematics teaching in primary schools. Whether it is the formation of mathematical concepts, the acquisition of mathematical conclusions or the solution of mathematical problems, it depends on the participation of computing activities. The quality of computing teaching will directly affect the learning of other contents. Through calculation teaching, students' thinking ability, psychological quality and study habits will be well developed. Computing teaching is often the most difficult knowledge for teachers and the most boring for students to learn. Since the curriculum reform, many teachers have deeply realized the importance of computing courses, and boldly tried many innovative methods in the classroom, trying to change the boring situation of computing courses and stimulate students' interest. However, it is not difficult to find that it seems that in actual teaching, students' calculation is not as ideal as the teacher imagined, and students' calculation speed is not very fast, making mistakes more easily. The reason for this is the following：

1, too many calculation errors are attributed to non-intellectual factors. Both teachers and parents blame students for the formation of good habits, such as careless attitude, carelessness and lack of inspection.

2. Improve the accuracy of calculation and overemphasize operability. Teachers often assign a large number of the same type of questions to practice repeatedly in the calculation class, and sometimes there will be a high-pressure policy of practicing more than one wrong question.

3. Arithmetic is contained in specific situations, which reduces the precision of arithmetic infiltration algorithm. Situation creation pays attention to superficial stimulation and novelty, and pays attention to too much non-mathematical information, which interferes with and weakens the learning of mathematical knowledge and skills and the development of mathematical thinking.

4. There are various algorithms, but there is a lack of communication between them. After listing the formulas, the students worked out the results from different angles according to their own experience. Teachers play one by one on the blackboard, which seems to reflect students' autonomy. In fact, the teacher didn't help students to communicate the internal relations between various algorithms, and lacked the refinement of calculation methods, which led to outstanding arithmetic, imperfect algorithms and unskilled students' skills.