First, the principle of fun, adjust the learning mood

Interest is the best teacher. Interest can play a directional, continuous and intensive role in students' learning, improve their interest in practice, make practice interesting, make practice interesting, not only reduce their psychological burden, but also change "passive learning" into "active learning", effectively improve the quality and effect of practice and truly achieve the purpose of practice. In practice, designing vivid and interesting exercises combined with students' existing knowledge can make students feel interesting and intimate about mathematics, which is helpful to improve their thinking ability and innovative consciousness in mathematics learning. For example, after learning the pie chart, you can design an exercise: let students take their own income as the total, calculate the percentage of expenditure of each part of the family, and express it with the chart they have learned. Students are very interested in arranging such exercises, not only reviewing what they have learned, but also applying what they have learned to their lives.

Second, the hierarchical principle reflects individual differences.

According to the content of teaching materials and the learning psychology of primary school students, homework design must vary from person to person, teaching students in accordance with their aptitude, from easy to difficult, from simple to complex. We should not only pay attention to poor students and middle school students, but also pay attention to top students, so that poor students can eat well and top students can eat well, so that different students can develop differently in mathematics. Let students practice at different levels, so as to promote their intellectual development. For example, in the new curriculum practice of "finding the reciprocal of a number", it can be divided into four levels: the first level allows students to find the reciprocal of integers and fractions according to the meaning of reciprocal; The second level, think about the reciprocal of 1 and 0. The third level, find the reciprocal of the decimal. In the fourth level, students report their own data, and then let other students do oral calculations to find the reciprocal of this number. In this way, students find it interesting and the classroom atmosphere is active.

Thirdly, the classification principle reflects the effectiveness of the exercise.

The law of children's cognitive development is from easy to difficult, from shallow to deep, step by step. Therefore, exercises with reasonable levels and various forms conform to students' cognitive laws. This requires teachers to design exercises effectively, change the traditional practice concept, establish efficiency consciousness, proceed from the present situation and start with "effectiveness", so that students can learn solidly and easily and realize the real "burden reduction effect". In a math class, whether the exercises are effective or not will be the finishing touch of a class. Therefore, when designing exercises, teachers should not only consider the practice methods as a whole, but also consider the specific content of exercises, and grasp the degree and quantity of exercises, so as to improve students' learning efficiency. According to different teaching contents, different purposes and different class types, the methods of practice design should be different.

Extended data:

The practical design of primary school mathematics practice course focuses on skills.

The practice class focuses on practice, which aims to enable students to further consolidate, understand and apply knowledge and form skills and techniques under the guidance of teachers.

(1) Consolidation exercise. The purpose of this exercise is to consolidate and strengthen new knowledge, which is a supplement and continuation of new teaching. If you have learned how to decompose decimals into integers, you can supplement the following exercises: 3 ÷ 8 =1.35 ÷15 = 0.49 ÷ 7 = 25.5 ÷ 3 = 7.2 ÷ 36 =? The purpose of this consolidation exercise is to deepen students' application of dividing decimals by integers, highlighting that the dividend is not quotient 1, and the dividend is added with a decimal point and supplemented by 0.

(2) variant exercises. This kind of exercise refers to changing the forms of things presented from different angles and in different ways, so as to reveal their essential attributes, and at the same time prevent students from forming negative "thinking patterns" and develop good study habits of thinking from all directions and angles. The design of variant exercises can be to change the form of expression, narrative way and graphic position.

(3) Comprehensive exercises. This kind of practice refers to the practice of skillfully combining old and new knowledge according to the teaching needs, which embodies the integrity and is convenient for students to compare; You can also organically combine old and new knowledge in one topic, which is convenient for students to see the correlation and cultivate their comprehensive application ability. For example, after learning the area of trapezoid, arrange a group of combined figures. Ask the students to find the area of the combined figure.