The common quantities in primary schools basically appear in the first period, mainly including monetary units, time units and weight units. This part of the revised curriculum standard has not changed much. However, in the past teaching, some teachers did not fully implement the specific requirements of understanding common quantities in the curriculum standards. For the teaching of this part of the content, some teachers just stay to let students know these common quantities and can convert them between simple units. Then, in view of this problem, how should we accurately implement the specific goal of understanding common quantities in classroom teaching?

(1) Based on the real life situation,

Help students understand common quantities.

Mathematics curriculum standards advocate students to feel mathematics in life situations. Professor Geng Shuang's grams and kilograms, and Professor Zhu Jie's cognition time, the first primary school affiliated to Beijing Xuanwu Normal University, can help students reflect and understand common quantities according to real life.

In the lesson of "grams and kilograms", Mr. Geng pays attention to relying on real life situations, introducing learning from the familiar life situations of students (all kinds of goods bought from supermarkets, common situations related to grams and kilograms in life), and revealing the learning content of this lesson. This introduction can better stimulate students' interest, at the same time give children the opportunity to discover math problems, and also let students feel the close connection between grams and kilograms and daily life.

In the lesson of "Knowing Time", Mr. Zhu combines knowing time with students' work and rest time at school, arouses students' existing and familiar life experience, and helps them to know clocks and watches and understand common time units.

(2) Relying on the actual activity situation,

Help students understand common quantities.

Practice is the best teacher, and students will be more impressed only by personal experience. Therefore, in addition to relying on realistic life situations, we can also rely on realistic activity situations to help students understand common quantities and establish a correct concept of quality and time.

For example, it is difficult for students to learn grams and kilograms. Although students have come into contact with quality problems in their lives and feel that they are too light and too heavy, and have seen kilograms and grams on commodity labels, most students do not know that they are quality units, nor do they know the progress between them, and even less about the weight of 1 gram or 1 kg. And people's perception of quality is not strong, the same things are weighed and lifted, left hand and right hand, everyone's tolerance and so on. And I feel the result is different. At the same time, the volume and mass of an object are not necessarily uniform, which makes it difficult for students to understand the unit of mass. In the process of teaching grams and kilograms, Mr. Geng, the first primary school affiliated to Xuanwu Teachers College, prepared a large number of operable items for students, leaving room for students to explore, so that students can know grams and kilograms through weighing and weighing activities in the process of feeling 1 kg and 1 kg, and at the same time help students establish a correct quality concept.

For another example, the understanding of time unit is a very abstract concept for students. Without visible and tangible shapes and colors, they are invisible and intangible, so it is difficult for them to grasp the abstract concept of time. Therefore, the development of children's sense of time must be related to specific events in daily life, so as to have practical content. What can students do after 1 minute in the course of "Knowing Time"? (You can bounce the ball a few times, jump rope a few times, and write a few times), so that students can experience, feel and understand how long 1 minute is, and help them establish the concept of time.

Third, the teaching suggestions about the commonly used quantities.

(1) strive for the cooperation and support of parents, and accumulate life experience for students to learn common usage in advance.

Because the common content of quantity is abstract for the students in the first period, whether they have enough life experience will affect the learning of this part of knowledge. If students can often come into contact with relevant knowledge in their daily life, they can learn well in this respect. For example, if students have the experience of shopping with their parents, it will be much easier to learn RMB. On the contrary, the lack of life experience will make it difficult for students to understand and cause learning difficulties.

(B) the use of a variety of teaching strategies, the common quantity and real life organically.

In teaching, we should pay attention to the use of various teaching strategies to make common quantitative learning closer to students. We should pay attention to providing students with a variety of learning materials, making full use of learning tools, mobilizing students' multiple senses to participate in learning, providing students with opportunities for hands-on practice, independent exploration, observation and thinking, discovery and expression, stimulating students' participation consciousness and enthusiasm, and letting students learn to use what they have learned to solve practical problems in practice.