Reflections on the teaching of "gram and kilogram" 1 gram and kilogram are two quality units that students have directly or indirectly contacted in their lives, but they are not as intuitive and specific as length units and cannot be obtained through observation. Therefore, the focus of this lesson is to establish the conceptual process of 1 g and 1 kg. This lesson mainly allows students to find that the quality of objects is closely related to life from common life scenes. At the same time, it pays attention to students' independent construction of concepts. Let students build their own knowledge system through full experience and exploration. The two quality units of "kilogram" and "gram" are put together in teaching, and they are understood and constructed as a whole to form a clear concept. Facts have proved that as long as students master one of the quality units, then another concept will naturally be mastered.
When establishing the concept of 1g, ask students to weigh a peanut about 1g, fully feel the weight of 1g, and give examples of many things weighing about 1g in life, so as to deepen their impression of grams. When I established the concept of 1 kg, I divided the content into layers and asked the students to weigh 500g and two 500g (1000g). Through a series of activities, we can fully feel the actual weight of 500g and two 500g (1000g). Then use the scale to verify that 1 kg is 1000 g, so that students can accurately establish the concept in the hands-on experience.
Students' understanding of grams and kilograms is far from enough if they only stay on the understanding of "1 peanut weight 1 gram" and "two bags of salt weight 1 kg". In order to organically link the teaching content with the quality of articles in life and make the abstract quality unit more vivid and concrete. I asked the students to estimate the weight of their familiar schoolbags, math books and pencil boxes, and then weigh them with a scale to verify whether the estimation is correct. Through these operations, students become more and more clear and profound about the quality concepts of grams and kilograms.
Therefore, this class should start with students' life and be close to life. Through students' personal experience, the distance between life and teaching materials can be shortened, which not only improves students' interest in learning, but also enables students to actively acquire new knowledge in class.
Reflections on the teaching of grams and kilograms 2. The primary difficulty in teaching comes from the psychological characteristics of students. For junior students, they often pay attention to the surface characteristics such as the size, length and even color of objects first, but not to the essence of weight, and some of them are indirect. It is very challenging for junior two students to establish the concepts of "gram" and "kilogram"
First, because students are less exposed to grams and kilograms in real life, second, students pay less attention to and experience weight in real life, and third, grams are relatively small, so students rarely feel and experience this weight unit. Therefore, in the teaching activities of this class, I first ask students to weigh the quality of a 2-cent coin and talk about their feelings. At first, they thought that 1 gram was a very light unit, and people could hardly feel it. After that, I asked the students to look for items weighing about 1g on the table, and exchanged estimation methods to cultivate their estimation ability, and then revealed that all the items found by the students weighed about1g. How many coins do students need to perceive 10g, 20 or 50g in order to enrich their perception of grams? And let a group of 6 or 8 students weigh together. How much do 20 grams, 50 grams and 100 grams weigh? Let students estimate the weight of apples and salt under the condition of complete perception, and pay attention to the optimization of estimation methods during the estimation process. Unfortunately, after estimating and determining the weight of the apple, I forgot to let the students feel the weight of 200 grams. When teaching 1kg, I asked the students to guess which is heavier 1kg rice or 1kg waste paper. Because of the big difference in volume between the two, students have a good understanding of kilograms and know that comparing the lightness and quality of goods is more important than volume. Finally, I asked the students to compare the difference between 1g and 1kg. They obviously felt that 1g was much lighter than 1kg, which laid a good foundation for them to choose suitable quality units in the future. Understand the relationship between grams and kilograms. Strengthen the understanding of grams and kilograms through various exercises.
After teaching kilograms, it is a pity that students are not allowed to feel the weight of dozens of kilograms because of time. It is also worth reflecting that in the process of returning to textbooks to sort out knowledge, ideas should properly guide students to sort out and review knowledge.
Reflections on the teaching of grams and kilograms 3. Perception in practice
How much does 1 gram weigh? How much does 1 kg weigh? I fully respect the students' existing life experience, and all the cited examples are often contacted or seen by students. Teachers and students work together to prepare enough teaching AIDS, learning tools and articles to mobilize a variety of sensory collaborative learning. Students estimate, weigh, weigh, compare and talk to feel the weight of objects. Students have personally experienced the actual mass of 1 g, a few grams and 1 kg, a few kilograms. This feeling is not instilled by the teacher, but by the students themselves. In the whole teaching process, students participate in learning activities by "doing" rather than just "listening" and "speaking". They not only understood the correct meanings of "gram" and "kilogram", but more importantly, they mastered the general methods of discovering, recognizing and understanding mathematics, and cultivated their exploration consciousness and innovative spirit.
Second, accumulate experience.
Experience is the emotion and consciousness produced by physical activities and direct experience, which makes learning enter the field of life. Because of experience, knowledge learning is no longer limited to the category of cognition and rationality, but extends to the fields of emotion, life and personality, so that the learning process is no longer just a process of knowledge growth, but also a process of physical and mental health and personality development. The experience of mathematics learning is a remarkable feature of modern learning methods.
In traditional teaching, the focus is generally on the conversion of units. In teaching, the method of teaching memory is often used. Students can complete the teaching task as long as they remember several commonly used quality units and can switch between them correctly. In this kind of teaching, students often joke after learning the quality unit: a watermelon weighs 3 grams, an egg weighs 50 kilograms, and Teacher Wang weighs 60 grams ... This reflects the serious disconnection between mathematics teaching and real life.
The teaching focus of understanding grams and kilograms is based on the concept of "how heavy is 1kg and 1kg", which attaches importance to both mathematical facts and mathematical experience. Therefore, in the "understanding of grams", I repeatedly ask students to weigh, estimate, weigh and find the quality of different objects in life, feel their quality and enrich their mathematical experience. This kind of feeling and experience is not only the basis for further study, but also the necessary skill for "learning to survive" in the future. The concepts of "gram" and "kilogram" are established in students' minds, and gradually formed through students' eye observation, ear listening, brain thinking, mouth expression, hands operation and mental perception, that is, through their own physical experience and experience, they will surely precipitate into students' hearts.
Reflections on the teaching of grams and kilograms 4 "Mathematics Curriculum Standards" points out that students' mathematics learning contents should be realistic, meaningful and challenging, and these contents should be conducive to students' active observation, experiment, guess, verification, reasoning and communication. Mathematics activities must be based on students' cognitive development level and existing knowledge and experience. According to the two basic concepts put forward by the new curriculum standard, I deeply realized in teaching:
First, use living teaching materials to induce learning motivation.
Textbooks present us with a kind of static knowledge, and the situation it creates is far from the reality of local students' lives. When preparing lessons, teachers should deeply understand the intention of compiling textbooks, creatively use textbooks and create familiar life situations and problem situations for students. Identify the "nearest knowledge growth area" and induce students' internal motivation to learn. In this class, I first let the students exchange some findings in their usual shopping. The students learned to know the quality labeling of goods, making them feel that the knowledge of grams and kilograms is true and cordial, which has built up enough confidence for the students to learn mathematics in our lives.
Second, provide students with the opportunity to "do math"
In traditional teaching, the process of knowledge formation is taught by teachers. Teachers' teaching replaces students' operation and thinking, and students can't experience the formation process of knowledge.
In this class, I fully provided students with the opportunity to "do mathematics" and let them actively construct knowledge. Students form the representation of grams and kilograms through the activities of weighing, guessing and weighing, and then fully weigh, feel and list many items weighing about 1 gram in life. Through a lot of calculations, such as weighing 2 cents, math books, 1 kg salt, schoolbags, etc. Students are becoming more and more clear and profound about the quality concept of grams and kilograms. Students gradually developed from "gram is light" and "1kg is a little heavy" to weighing, estimating and knowing the mass of objects with springs. Mathematics in these lives is not taught by teachers, but experienced by children themselves, forming certain skills and gaining positive emotional experience.
Third, broaden the free space for students to experience.
Students' understanding of grams and kilograms is far from enough if they only stay on the understanding of "1 twenty-cent coin weight 1 gram" and "two bags of salt weight 1 kg". In teaching, teachers should give full play to students' learning potential, mobilize all kinds of senses to actively participate and broaden students' experience space.
In this lesson, students weigh 2 cents, that is, math books, pencil boxes and other items weighing less than 1 kg, and then weigh the items weighing more than 1 kg in groups. In group activities, students work together, some change things, some look at the pointer, and vivid "shopping scenes" reappear. What's more gratifying is that in the process of knowledge exchange and ideological collision, students realized that there are both large and small objects weighing 1 kg, which broadened their experience space.
Reflections on the teaching of grams and kilograms. A preliminary understanding of grams and kilograms Unit 6. Gram and kilogram are a brand-new quality concept for primary school students. Gram and kilogram are two basic units of mass, but the unit of mass is not as intuitive and specific as the unit of length, so it can't be observed with eyes, and can only be perceived by muscle feeling. According to the psychological characteristics, age characteristics and actual life experience of primary school students.
In order to let students know the actual weight of each unit and apply it in practice. I will convey the fact that life is long and short, and there are more and less; Two students, one big and one small, were invited, which led to the difference between the two students and introduced the quality. Then ask the students to exchange the information collected by shopping or show the real thing. Select rice weighing about 1g and fruit (4 apples) weighing about 1kg, hold an object in one hand, and compare the objects weighing about 1g and 1kg, thus establishing the concept that "gram" is lighter than "kilogram". Then use the accumulated feeling to find articles about 1 g and 1 kg; In this class, I fully provided students with the opportunity to "use mathematics" and let them actively construct knowledge. Provide students with as many physical materials as possible, so that students can form the representation of grams and kilograms through practical activities such as weighing, comparing, guessing, saying and weighing, and then fully weigh and feel, and list many physical objects in life to increase students' perceptual knowledge. Such as: 1 kg of apples, how many are there, how much is 500g of salt, 1 pencil box, 1 child, 1 watermelon, 1 table tennis, 1 piece of chalk, etc. Let students perceive the quality unit, and then go to 65438. Knowing 1 kg = 1000 g makes students more and more clear and profound about the concepts of grams and kilograms. From the initial appearance of "gram is light" and "kilogram is slightly heavy", it has gradually developed into weighing, estimating and knowing the quality of goods with a scale. Mathematics in these lives is not taught by teachers, but experienced by children themselves. They form certain skills and gain positive emotional experience.
Reflections on the teaching of grams and kilograms 6 grams and kilograms are the first quality units that students come into contact with, and we often have to deal with them in daily life, but students' understanding of quality units is still very lacking. So this lesson introduces the topic from shopping, so that students can know all kinds of scales, and then perceive 1g and 1kg in practice. Through eye observation, hand perception, hand operation, brain thinking, ear listening and speaking and other activities, students can experience the actual mass of 1g, several grams and 1kg, and feel the weight of the object, so that students can establish a clear concept of quality in their minds from different angles. Finally, I returned to my life, found out which things around me can be measured by grams and which things can be measured by kilograms, understood the correct meaning of grams and kilograms, and realized the idea that mathematics comes from life and returns to life.
Disadvantages of this lesson:
1, give students a short time to weigh, feel and find. 1g, 1kg can't just be said by the teacher in class. Understanding them requires children's own feelings. Students have more time to weigh, find and feel all kinds of articles about 1 g. However, for some reason, when teaching kilograms, students are only allowed to weigh two bags of salt and four big apples in class. The experience time of students is really short.
2. The students' experience in grams and kilograms is not rich enough. Judging how many grams and kilograms there are, there is a big error between the estimated value and the actual value, which shows that the establishment of students' concept of grams and kilograms needs to be promoted through more practical activities, and teachers' flexibility and adaptability to classroom problems need to be improved and strengthened!
Suggestion:
Let the children go to the supermarket again this week to see how many grams there are on the small food bag; Looking at the kilograms of rice, flour, electrical appliances and other bulk commodities, children's horizons will be broader, their knowledge will be solid, their use will be skilled, and their living ability will be improved.
Reflections on the teaching of grams and kilograms. Starting from the practical problems in life, students can be inspired to know the unit of mass, but the unit of mass is not as intuitive and specific as the unit of length, so they can't observe it with their eyes, but can only feel it with their muscles. Therefore, with the aid of teaching AIDS and multimedia courseware, students can intuitively feel the concepts of 1 g and 1 kg, and cognize and construct them as a whole to form clear concepts.
At the same time, when establishing the concepts of 1 g and 1 kg, I pay attention to my classmates' inquiry experience. Ask the students to guess, weigh and weigh the quality of a paper clip, fully feel the weight of 1 gram, and cite many items weighing about 1 gram in life, which deepens the impression of grams. When establishing the concepts of 50g, 1 00g and1kg, I made the general unit of mass more specific. I asked my classmates to weigh, evaluate, compare, talk and weigh what they brought. Through these operations, their concept of grams and kilograms became clearer and deeper. From the initial appearance of "gram is light" and "1kg is a little heavy", students gradually developed to weigh, estimate and recognize the quality of goods with springs, gradually formed certain skills and gained positive emotional experience. I pay more attention to the transfer of knowledge when teaching the letters of kilograms and grams and the calibration of spring scales. In this way, teachers can correctly grasp the degree of knowledge imparting and inquiry experience in a class, so that students can learn more happily and independently. However, there are still some students who have a poor understanding of the unit grams and kilograms of quality and have not carefully experienced them in their lives. In the future study, we should cultivate students' habit of being good at observation.
Reflections on the teaching of grams and kilograms 8 In the teaching of grams and kilograms, I think the primary difficulty in teaching comes from the psychological characteristics of students. For junior students, they often pay attention to the surface characteristics such as the size, length and even color of the object first, and pay less attention to the essence of weight. It is very challenging for junior two students to establish the concepts of "gram" and "kilogram" First, because students are less exposed to grams and kilograms in real life, second, students pay less attention to and experience weight in real life, and third, grams are relatively small, so students rarely feel and experience this weight unit. Therefore, in the teaching activities of this class, we strive to embody the following two aspects:
1, to arouse students' attention to the weight of objects in certain situations;
2. Let students feel and experience through operation and practical activities, and initially establish the concepts of "gram" and "kilogram".
Therefore, the orientation of my teaching goal in teaching design is:
1, in specific life situations, let students feel and know the weight unit grams and kilograms, initially establish the concepts of 1 grams and 1 kilograms, and exchange the relationship between grams and kilograms, so as to know 1000 grams = 1 kilograms and know their differences.
2. On the basis of establishing the concept of weight, cultivate students' awareness of estimating the mass of objects. After teaching, I reflected on this class.
One of reflection-let students fully carry out psychological activities such as imagination, reasoning, guessing and judgment, and challenge their own thinking. For example, at the beginning of class, ask students to talk about heavy items, light items and how heavy these items are. Can you tell me that this has not only aroused students' further concern about weight, but also mobilized the existing knowledge and experience about weight units? Although the students didn't speak tons of knowledge, it provided important information for teachers' next teaching implementation. When students establish the concept of "1 g", it is very important for students to establish the concept of "1 kg". The order from ten grams to dozens of grams and then to hundreds of grams is very important for students and can be established by combining their own practical experience. From the perspective of teaching practice, I showed a group of projects with weighted order for students to guess and make reasonable guesses. After students first notice the weight of objects, let them boldly estimate the weight of these items. Although the weight estimated by students does not meet the actual standard answer, the difference is not very big, but the most important thing is to let students have a strong demand to know the actual weight of this item, so as to bring out a simple sequence of object weight units. The main purpose of the sequence is to let students feel the weight of the object initially but truly in teaching, and at the same time "construct".
The second reflection-in this class, in order to arouse students' attention to weight, the situation created is relatively open, so the teachers who organize the implementation are required to be higher, especially the artistry and standardization of classroom teaching. Unexpectedly, when I asked a student to weigh the object on the stage, some students didn't listen carefully and said that I didn't let him on the stage. I didn't expect that. In class, students see the scale for the first time and feel very fresh. When weighing, they only "studied" the scale, and finally, under the guidance of my "long-awaited", they focused on the weight of the object.
The third reflection-encouraging language students to learn provides a situational field. Teachers' evaluation will have a great influence on students' learning psychology, and exercise opportunities will make students more engaged and learn more effectively. In the classroom, students can make bold guesses, gradually approach the standard answers, ask quality questions under the encouragement of aggressive psychology, and maintain good learning interest and positive learning mood without the encouragement of teachers' language. In this class, the teacher made a positive evaluation of the students' situation that appeared at any time in the class. This dynamic and generative evaluation effectively promotes students' positive thinking and emotion. For example, when the teacher asked the students to guess the weight of a big bag of monosodium glutamate, some students couldn't help screaming that they already knew the answer. The teacher quickly answered the question and asked them how they knew. The students said excitedly that they peeked before class. The teacher had a brainwave and let them write happily on the blackboard, which naturally and harmoniously generated the content of the next link, and the students were encouraged. Encouraged by the teacher, students ask quality questions from time to time. For example, students ask: Why does one pack of monosodium glutamate use grams as the unit and the other pack uses kilograms as the unit?