The teaching goal of sorting out the application problems of scores and percentages in supermarket mathematics is 1. Sort out the students' existing knowledge, so that students can understand the ideas and methods of solving fractional and percentage application problems, and form a certain knowledge network and mathematical skills on this basis. 2. Cultivate students' awareness of "using mathematics" and their ability to solve practical problems. 3. Cultivate students' ability to use knowledge flexibly to solve practical problems and experience the new concept that mathematical knowledge comes from practice. Teaching focuses on mastering the quantitative relationship and problem-solving rules of three types of application problems. Combing and summarizing three kinds of application problems in teaching difficulties. Teaching process 1. Dialogue presenter: All the students visited the supermarket. There are not only delicious food and drinks in the supermarket, but also rich learning resources. Today, in this class, let's go to Hualian Supermarket to get information and use the knowledge of scores and percentages to solve some practical problems in the supermarket. 1. Please read these three pieces of information first and say what you know and what you associate. (1) The turnover of food accounts for 85% of the total turnover; (2) The number of people shopping in Hualian Supermarket on weekends is 30% more than usual; (3) During the National Day, the microwave oven made a profit of 5%. 2. Summary of teachers and students * * * By reading these sentences containing fractions, we can know that one quantity is the unit "1", and we can associate another quantity with a fraction of the unit "1". You can also write a basic quantitative relationship: unit "1"× fraction = corresponding quantity. Using this quantitative relationship, we can solve many practical problems. (blackboard writing) unit "1"× score = corresponding quantity 2. Organize and summarize 1. Sort it out and find out what percentage of one number is another. Questioner: I found two messages in the toy section of the supermarket. What math questions can you ask about fractions and percentages? (Write the questions according to the students' answers) The price of each football is 120 yuan. The price of each basketball is 200 yuan (1). Students can ask questions freely. The teacher writes and shows ① What percentage is the price of each basketball? (2) What percentage of the price of each football is that of each basketball? ③ What percentage is the price of each basketball more than that of each football? How much is the price of each football less than that of each basketball? ⑤ What percentage of the total football and basketball is the price of each football? 6. What percentage of the total football and basketball is the price of each basketball? (2) Choose two typical questions, ask students to list formulas in their notebooks, and name the rest by students. Only formulas don't count. (3) Thinking and summary: What are the similarities in answering the above questions? What are the similarities between the quantitative relations of these problems? What types of application problems can be summarized? (Teacher and student * * * Summary: To solve the application problem that one number is the percentage of another number, we must first find out which two quantities are compared, and then identify the quantity with the unit "1", and then carry out continuous calculation. (blackboard writing) Find an application problem in which one number is a few percent of another. 2. Sort out the application problems of a number and a known number, and find the application problems of this number. Teacher: My uncles and aunts in the supermarket know that our classmates are learning about fractions and percentages, so they specially wrote several related questions and wanted to test our classmates. How's it going? Let's have a try. (1) Show some questions about supermarket information arrangement, and let students examine the questions independently first. (1) Hualian Supermarket has 360 employees, of which the food department accounts for the total number. How many employees are there in the food department? (2) Teacher Wang bought a box of juice at the price of 60 yuan in Hualian Supermarket, and just used the money he brought. How much did Teacher Wang bring? ③ A rice cooker, the price of Hualian Supermarket 130 yuan, the price of Honglian Supermarket is more expensive than Hualian Supermarket 10%, how much is Honglian Supermarket? ④ During the promotion period, the price of each microwave oven is 480 yuan, which is 40% lower than the original price. What is the original price? (2) Group communication: Can these questions be divided into two categories? What is the reason for your classification? What is the difference between the first type of questions and the second type of questions? (3) Feedback the answers to the application questions and find out the reasons for the mistakes. (4) Summarize the classification methods and reasons. According to the students' answers on the blackboard, what is the percentage of a number (the unit "1" is known and calculated by multiplication. ) Know the percentage of a number (a few), find this number (the quantity of unit "1" is unknown, and solve it by division or equation. ) (3) Teacher-student summary: Through sorting, we know that the application problems of scores and percentages can be divided into three categories. What do you think are the steps to solve these application problems? What's the point? According to the students' answers to the blackboard, the steps to solve the problem are as follows: 1. Read the stem and determine the unit "1"; 2. Find out the corresponding scores and think about the quantitative relationship; 3. Calculate in the form of columns; 3. Test and write the answer; 3. Comprehensive training Just now, uncles and aunts in the supermarket, I have several math problems about the supermarket here to see how our classmates are capable. See who can pass me. 1. Select the corresponding formula according to the conditions (gesture). Crystal pears cost 28 yuan per kilogram. What's the price of apples per kilogram? (1) is 25% cheaper than a kilo of apples (2) is 25% more expensive than pears (3) is 25% of a kilo of apples (① 28× (1+25%) ② 28× 25% ③ 28 ÷ 25% ④ 28 ÷ (6549.1998888888885 ⑥28-28×25% display problems. After reading the questions, the students will make gestures to indicate the answers. Give reasons to the wrong students. 2. According to the supplementary conditions of the formula, the price of "Philips" desk lamp is 60 yuan, and what is the price of "Mei Jia" desk lamp? After 60× 90% 60× (1+10%) 60 ÷ (1-10%) put forward questions and requirements, please ask the students to think independently before taking the roll call to answer them, and the rest of the students will evaluate them. 3.？ Let the students think about how to supplement the conditions and questions first, and then call the roll. The rest of the students listen to the formula or cooperate at the same table, then supplement the conditions and questions respectively, and then exchange answers. Finally, the whole class communicates. 4. Make an appropriate evaluation according to the students' answers. Summarize what you learned today. What's new? 5. To solve practical problems, please ask the business manager of Hualian Supermarket for advice. The cost per barrel of a detergent is 10 yuan, and the retail price is 65,438 yuan. The cost per vial of detergent is 65,438 yuan +0.2 yuan, and the retail price is 65,438 yuan +0.5 yuan. There are two schemes for the recent "Welcome the New Year" commodity preferential activities: the first scheme: the price of washing powder per barrel is 65,438 yuan. Option 2: sell at the original retail price, buy a bucket of detergent and give it away for free 1 small bottle of detergent. Please analyze it from a mathematical point of view to help the business manager of the supermarket come up with an idea and choose a plan. Review classes are also full of flowers. The application of fractions and percentages is one of the emphases and difficulties in this textbook. How to cultivate students' ability to solve this kind of application problems is a major issue for our graduating math teachers. The review class I designed today is intended to arouse everyone's topic and discuss the classroom teaching of primary school mathematics review class. 1. The comprehension scores and percentage application questions of the textbook are distributed in the four units of the teaching content in Volume 1 1. It includes three categories, one is to find the fraction and percentage of one number to another, the other is to find the fraction and percentage of a number, and the third is to find the fraction and percentage of a known number. These three types of application problems are distributed in the learning content of four units. The arrangement of teaching materials, from easy to difficult, is conducive to students' gradual understanding and mastery of fractional and percentage application problems. In teaching, students should not only understand the quantitative relationship of each type of application problems and the connections and differences among the three types, but also use what they have learned to solve some practical problems in life and realize the wide application of percentages in life. Therefore, when I choose the course "Sorting and Reviewing Fractions and Percentages Application Problems", my goal is to sort out the students' existing knowledge, so that students can understand the ideas and methods of solving fractions and percentages application problems, and form a certain knowledge network and mathematical skills on this basis. Cultivate students' awareness of using mathematics and their ability to solve practical problems. Cultivate students' ability to use knowledge flexibly to solve practical problems, and experience the new concept that mathematical knowledge comes from practice. Second, the content of the new curriculum standard of primary school mathematics emphasizes the connection between mathematics and real life, and requires that "mathematics teaching must start with the familiar life situations and things that students are interested in", so that they can realize that mathematics is around, feel the role of mathematics and experience the charm of mathematics. Therefore, when I design this review class, I try my best to embody this idea. As the saying goes, a good beginning is half the battle. The first link is the beginning of a class. If the guidance is in place, it will greatly mobilize students' enthusiasm for learning and ensure the smooth development of the class. So I use the introduction of dialogue, starting from the supermarket that students are familiar with and love, saying, "There are not only delicious food and good drinks in the supermarket, but also rich mathematics learning resources." Introduce students' ideas into mathematics classroom. Then display information in a group of supermarkets, and review the quantitative relationship between scores and percentage application questions through students' observation and discussion. The second link is to summarize and sort out the types of basic application problems. In order to make students fully master knowledge and internalize it into a complete knowledge system, our review class must be comprehensive and systematic. However, in the review, we can't repeat the knowledge step by step according to the book arrangement, nor can we repeat the exercises in the sea tactics in large numbers. In order to prevent students from being depressed, bored, time-consuming and laborious after eating a cold meal, the effect is low. Our teachers should reasonably and effectively help students systematically sort out the basic knowledge, internalize the knowledge structure, enhance students' active participation in learning activities, and let them find problems, ask questions, think, discuss and analyze, and finally draw conclusions and use them flexibly. In this link, what I want to do is to lead students to sort out three types of application problems and summarize their basic characteristics and problem-solving ideas. The new curriculum concept emphasizes the development of students' subjectivity and the cultivation of innovative spirit. The original intention of my design is to let teachers provide materials, so that students can summarize the problem-solving methods of three basic application problems, score and percentage, and build a knowledge network by compiling questions, answering, summarizing, classifying, sorting and summarizing themselves. In the third part of this lesson, in order to strengthen the review of the basic types of fractional and percentage application problems, I designed a set of incomplete application problem models. The material of these questions is also taken from the supermarket, which conforms to the psychological characteristics of students. The purpose is to effectively build a bridge between mathematics and life, so that students can feel that learning mathematics can solve some practical problems in life, so that students can learn to observe and analyze problems in real life from a mathematical perspective and experience the value of mathematics. In this link, I designed three levels of questions. The first level is to let students choose the formula according to different situations. The second level is to let students supplement the conditions according to the specified formula. The third level is to give only one known condition, so that students can supplement the conditions and questions. The difficulty of the three-level model is increasing in turn, the space for asking questions is also expanding in turn, and the thinking space of students is also expanding and opening up. The fourth link is for students to sum up the gains of this class. After studying for such a long time, I arranged such a summary exchange. On the one hand, it is to let students summarize and review their own learning, on the other hand, it is also to let students listen to others' learning gains and let everyone share the joy of learning. After class, I also arranged an operation to solve practical problems, so that students could help the business manager of the supermarket with ideas everywhere. This topic comes from the reality of life, and students should relish it, and their enthusiasm for exploration will not decrease, which will help students deepen the review content of this lesson and lay a good foundation for the next math study. It turns out that math learning can be so interesting and vivid! 3. Thinking about design When designing this review class, I think more about how to arouse students' enthusiasm for learning and how to make our students explore actively. For a long time, everyone seems to have such a * * * knowledge: new teaching needs students to explore, new teaching needs to create situations, new teaching can fully reflect students' innovative thinking, and new teaching is easier to succeed and more glorious. In fact, our practice class and review class also need students' inquiry and a suitable situation. If carefully designed and guided, the sparks of students' innovative thinking will shine and the classroom will shine as it should. With such a good wish, the difficult journey of preparing lessons began. What you see now is not the lesson plan I prepared for the first time. At first, I was completely immersed in the review and arrangement of application problems, thinking about how to find out typical application problems that can represent various basic problems, so I had a review teaching plan with complete knowledge system, rich practice structure and obvious pure mathematics taste. When I was still complacent, Teacher Chen woke up the dreamer with a sentence, "Will the children like this class?" Will they have the enthusiasm for learning? "I am facing a group of children full of childlike innocence, not a group of young mathematicians. Should such a review step be designed? What kind of attitude will students take to study? I started thinking all day and all night again, and finally, I had the idea of "going to the supermarket." The final version of "Mathematical Problems in Supermarket", a situation runs through the whole class. Without too many other decorations, a few words can bring our innocent children into the supermarket situation and let students start math learning happily. All the application problem models in this lesson are based on the specific environment of the supermarket. I don't think creating a situation is necessarily a fancy arrangement or fancy dress, just like what we did in this class is also creating a situation. As long as it can arouse students' enthusiasm for learning, whether there is multimedia or courseware is not the key. The key lies in whether our teachers study the textbooks attentively, and whether we study and teach attentively. 4. After-class reflection class changes rapidly, and students are witty and lively, which determines that our teachers must be flexible. No matter how good the preset before class is, it can only represent our beautiful original intention; No matter how wonderful the review and reflection after class is, it can only be left to the next practical exploration. Opportunities for education are often fleeting. Who can grasp the classroom generation, adjust the classroom process at any time, change the teaching plan in time, and find the most suitable teaching method for students, will truly become the master of the classroom and truly make the classroom bloom with the most beautiful brilliance. Too bad I'm not. I can only say that I am trying to look forward to such a class and become the master of such a class in my lifetime. There is a saying: take it from it and use it. With such a high goal, I think I can achieve something one day. "Education takes a lifetime, and you know what you have gained and lost." Although the current classroom is not as I wish, I believe that through continuous efforts, continuous classroom practice, continuous reflection and exploration, coupled with the careful teaching of predecessors, I will certainly be able to learn and teach.